Serum 2

Serum 2 plug-in for Microsoft Windows and Apple macOS

A synthesizer instrument plug-in for VST3, Audio Unit, and AAX hosts

Version 2.0.18
Manual Version: 1.0.3
April 27, 2025

Serum 2 Development Team

Oli Cash
Nick Dowell
Steve Duda
Dave Gamble
Damon Hancock
Lance Thackeray

With special assistance from:

Matt Aimonetti
Laurent de Soras
Andrew Simper
Yan Lhert

Manual: John Jerney

Special thanks to:

Jeff Rona
Joel Zimmerman
David Alexander

Copyright © 2014-2025 Xfer Records, Inc. All rights reserved.

The information contained in this document is subject to change without notice. In no event shall Xfer
Records or the author of this document be liable for any damages arising out of or related to this docu-
ment or the information contained within it. No part of this document may be reproduced or transmit-
ted in any form or for any purpose without the express written consent of Xfer Records.

VST Plugin technology by Steinberg

VST is a trademark of Steinberg Media Technologies GmbH. All other copyrighted trademarks belong to
their respective owners.

WWW.XFERRECORDS.COM

Serum 2 User Guide 2

Table of Contents
Welcome 13
Registering Serum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Getting in Touch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Downloading Serum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Installing Serum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Installing on macOS and Windows-based PCs . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Uninstalling Serum on Windows-based PCs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Uninstalling Serum on macOS Computers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Exploring Serum 16
Exploring Sound Design in Serum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Getting Started 18
Adding Serum to a Track . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Loading a Serum Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Creating a New Sound . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Saving Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Embedding Content When Saving a Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Dragging Audio to Your DAW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Exploring Basic Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Displaying Help (Tooltips) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Using the Serum Keyboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Using Knobs and Sliders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Undo and Redo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Controlling the Main Output Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Using Oscillators and Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Enabling an Oscillator or Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Choosing Oscillator or Filter Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Using Pitch Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Routing an Oscillator or Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Accessing the Oscillator or Filter Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Resizing the UI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Using Wavetable Oscillators 37

What is a Wavetable? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Anatomy of a Serum Wavetable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Serum 2 User Guide 3

 Using Wavetables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Exploring the Waveform Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Randomizing the Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Setting Phase Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Wavetable Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Unison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Warp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Using Multisample Instruments 58

Selecting a Multisample Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Setting the Multisample Envelope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Velocity Track . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Random . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Setting Multisample Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Timbre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Unison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Warp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Switching the Last Note Played to a Sample . . . . . . . . . . . . . . . . . . . . . . . . 67

Using Sample Instruments 68

Selecting the Sampler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Setting the Sample Start and End . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Performing Sample Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Slicing Samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Loop Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Setting the Loop Start and End . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Setting the Crossfade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Setting Sample Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Scan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Unison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Warp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Switching a Sample to a Wavetable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

Serum 2 User Guide 4

Using Granular Synthesis 85
Selecting Granular Synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Setting the Sample Start and End . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Performing Granular Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Loop Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Setting the Loop Start and End . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Setting the Crossfade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Window Amount . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Unison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Setting the X|Y Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Setting Granular Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Warp Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Scan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Setting the Grain Randomization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Switching a Sample to a Wavetable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

Using Spectral Synthesis 104

Selecting Spectral Synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Setting the Sample Start and End . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Setting the Sample High and Low Frequencies . . . . . . . . . . . . . . . . . . . . . . . . . 107
Performing Sample Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Loop Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Setting the Loop Start and End . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Setting the Crossfade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Unison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Setting the X|Y Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Setting Spectral Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Scan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Cut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Mix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Setting the Warp Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Switching a Sample to a Wavetable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

Serum 2 User Guide 5

Using the Sub Oscillator 123
Exploring the Sub Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
Pitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

Using the Noise Oscillator 128

Exploring the Noise Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Loading a Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Loading a Sample . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
One Shot/Looping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Random . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Pitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Fine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

Using the Filter Modules 133

Exploring the Filter Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
Routing an Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
Filter Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
Filter Types and Var Parameter Functions . . . . . . . . . . . . . . . . . . . . . . . . . 135
Filter Display Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Setting Filter Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Cutoff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Resonance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
Fat (and Others) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
Pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Mix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Using the Mixer 144

Exploring the Mixer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Sending to the Busses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Setting Pan and Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

Serum 2 User Guide 6

 Mixing Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
Routing to the Busses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Setting Pan, Mix and Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Mixing the Busses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
Setting Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
Setting the Main and Direct Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151

Using Serum FX 152

Using the FX Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
Selecting a Rack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
Loading Rack Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
Adding Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Reordering Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
Copying a Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
Bypassing a Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Removing a Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Saving a Rack as a Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Exploring FX Rack Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Modulating FX Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Exploring FX Module Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
Exploring Individual FX Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Bode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Chorus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Compressor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Convolve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
Distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Equalizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
Flanger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
Hyper/Dimension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Phaser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
Reverb . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
Splitter L/H . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
Splitter L/M/H . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
Splitter MS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
Utility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182

Serum 2 User Guide 7

Exploring Sound Modulation 183
Using Envelopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
Configuring Envelopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
Modifying Envelopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186
Assigning an Envelope to a Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
Using LFOs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188
Configuring LFOs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188
Drawing an LFO Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
Modifying LFOs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
Assigning an LFO to a Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
Setting the Modulator Depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
Setting Negative Modulation Depths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
Copying a Wavetable Shape to an LFO . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
Copying an LFO Shape to a Wavetable . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
Modulating LFO Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
Modulating LFO Points Using Menus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199
Modulating LFO Points Using Drag and Drop . . . . . . . . . . . . . . . . . . . . . . . . . . 200
Using Context Menus with Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200
Setting Velocity and Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
Velocity Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
Note Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Using Macros . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Assigning a Macro . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
Using Oscillators and Filters as Modulation Sources . . . . . . . . . . . . . . . . . . . . 208

Using the Modulation Matrix 209

Exploring the Modulation Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
Moving Modulations in the Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Bypassing a Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Removing a Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Performing Matrix Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214

Setting Voicing and Portamento 215

Voicing Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Mono . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Legato . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Poly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216

Serum 2 User Guide 8

 Portamento Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217
Porta . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Always . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Scaled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218

Using Clips 219

Exploring the CLIP Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
Setting Global Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
Creating a New Clip Bank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
Saving Clip Banks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223
Working with the Piano Roll . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224
Setting the Grid Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
Zooming the Piano Roll . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
Folding the Piano Roll . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Managing the Clip Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
Configuring Clip Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
Managing Clips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Triggering Clips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
Recording Your Clips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
Managing MIDI Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
Routing MIDI to Another Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
Configuring the Clip Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
Using Macros . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241

Using the Arpeggiator 244

Exploring the Arpeggiator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245
Setting Global Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
Creating a New Arp Bank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
Saving Arp Banks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
Setting the Arp Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Creating a Custom Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249
Loading a Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249
Creating a New Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
Configuring the Pattern Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
Saving a Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Renaming a Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Using the Arp Graph Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
Transpose Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254

Serum 2 User Guide 9

 Playback Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
Retrigger Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262
Velocity Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262
Managing Arpeggiators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
Triggering the Arpeggiator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264
Managing MIDI Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
Configuring the Arp Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266

Using the Keyboard 267

Transpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
Setting the Key and Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268
Setting Swing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
Oscillator Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269

Using the Wavetable Editor 274

Using the Thumbnails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
Using the Drawing Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276
FFT Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
Managing Frames (Subtables) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281
Exploring Common Frame Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281
Copying and Pasting Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282
Inserting and Removing Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282
Sorting Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Using the Formula Parser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Exploring the Menu Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Importing a Wavetable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285
Exporting a Wavetable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285
Single Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286
All Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Morph Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
Saving Wavetables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290

Importing Audio as Wavetables 291

Understanding Multi-cycle Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . 291
Importing Multi-Cycle Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291
Advanced Imports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
Text File Overrides for Specific Results (Advanced) . . . . . . . . . . . . . . . . . . . . . . . 295
Importing Single-Cycle Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
Using the Import Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298
Creating a Sound Specifically for Serum Import (Advanced) . . . . . . . . . . . . . . . . 298

Serum 2 User Guide 10

 Importing an Image File as a Wavetable . . . . . . . . . . . . . . . . . . . . . . . . . . 300
Embedding Wavetables When Saving a Preset . . . . . . . . . . . . . . . . . . . . . . 302

Using the Formula Parser 304

Basic Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304
Built-in Binary Operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
Constants and Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
Exploring the Formula Presets Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Saving Your Own Formulas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
Managing Formula Files Manually (Advanced) . . . . . . . . . . . . . . . . . . . . . . . . . . 308
Exploring Formula Parser Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309

Exploring Global Settings 312

Using the Global Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312
Preferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313
Setting the Voice Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 316
Loading a Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 316
Creating a New Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317
Configuring the Voice Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317
Setting Randomization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
Setting the Scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
Saving the Voice Control Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319
Setting the Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319
Setting the Tuning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320
Setting Concert Pitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320
Using a Tuning File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320
Using MTS-ESP to Set the Tuning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321
Locking the Tuning Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321
Checking the Build Version and Date . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322

Appendix A: Using the Main Menu 323

Appendix B: Using the Presets Browser 327

Navigating the Folders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327
Loading a Preset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328
Previewing Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328
Searching Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
Searching by Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
Searching by Categories or Tags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
Searching by Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330

Serum 2 User Guide 11

 Managing Your Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Displaying and Editing Preset Metadata . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Specifying the Category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
Rating Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 333
Performing Standard Preset Operations . . . . . . . . . . . . . . . . . . . . . . . . . . 334
Creating and Exporting a Pack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337

Appendix D: Editing the Serum Preferences File 340

Changing the Default Artist Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340
Enabling Preset Changes using a MIDI Controller . . . . . . . . . . . . . . . . . . . . . 341
Using Notes to Trigger Preset Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 342
Enabling Oscillator Preset Changes using a MIDI Controller . . . . . . . . . . . . . . . 342

Appendix C: Exploring the Serum File Structure 344

Appendix E: Creating Wavetables 346

What Makes for a Good Wavetable? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 346
Table Ordering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 346
Interpolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347
Creating Wavetables from Scratch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347

Appendix E: Optimizing Serum 348

Exploring CPU Optimization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348
Managing Unison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348

Appendix F: Keyboard Shortcuts 349

Presets and Presets Browser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349
Controls (Knobs and Sliders) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349
Modules (Oscillators and Filters) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349
Sample/Granular/Spectral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
Audio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
FX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351
LFOs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351
Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351
Clips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352
Clips (Note Movements) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352
Clips (Note Operations) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 353
Wavetable Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 353

Additional Credits 354

Serum 2 User Guide 12

Welcome
Welcome to the Serum 2 User Guide. Serum 2 is an advanced virtual synthesizer that offers a unique
blend of sound generation methods together with a powerful modulation system.

Note: Throughout this manual, we’ll refer to Serum 2 (the latest version of Serum) simply as Serum.

Serum combines wavetable, subtractive, multi-sampled, sampled, granular, and spectral synthesis into an
intuitive and cohesive workflow. This manual helps you get the most out of your instrument.

Serum Main Screen

Registering Serum
If you purchased Serum through Xfer Records, you are automatically registered for free updates.

If you purchased Serum through Splice.com, registration is automatic with the email you used at the
time. If you are having trouble locating your registration on xferrecords.com, use the contact form
and mention your Splice username.

Serum 2 User Guide 13

 Welcome

Getting in Touch
If you have any feedback about Serum, wish to pass on your comments regarding the software or this
manual, or would like to send links to cool tunes made with Serum, please reach out to:

https://support.xferrecords.com

Downloading Serum
To download Serum, navigate to www.xferrecords.com, sign in to your account, and choose Your
Account in the user menu.

The account page appears.

All installers for your registered Xfer Records

products are available on this page.

Download the installer for your operating system.

Xfer Records User Menu

Installing Serum
Serum is available for both Apple macOS and Microsoft Windows. Serum is designed to be used within
a host audio application that supports the VST3, AU, or AAX plug-in formats.

Important: You must select the VST3 version when installing the AU or AAX version of the plugin.

Installing on macOS and Windows-based PCs

1. Navigate to the folder to which you downloaded the software and double-click the file to launch
the installer.

A wizard guides you through the installation.

2. Follow the steps and complete the installation.

3. Open your DAW and rescan/refresh the plug-ins.

Refer to the documentation that came with your DAW for details.

Serum 2 User Guide 14

 Welcome

Uninstalling Serum on Windows-based PCs

1. Delete the Serum 2 folder from the following folder:

C:\Users\(username)\AppData\Roaming\Xfer\

2. Delete the Serum 2 Presets folder.

If you have Microsoft OneDrive enabled, delete the Serum 2 Presets folder in the following
location:

C:\Users\(username)\OneDrive\Documents\Xfer\

Otherwise, delete the Serum 2 Presets folder in the following location:

C:\Users\(username)\Documents\Xfer\

Note: Serum does not modify the Windows registry, therefore, you do not need to run an uninstaller
application to completely remove Serum from your system.

Uninstalling Serum on macOS Computers

To uninstall Serum on macOS, remove the Serum 2 files and folders from the following locations:

• /Library/Audio/Plug-Ins/VST3/

• /Library/Audio/Plug-Ins/Components/

• /Library/Audio/Presets/Xfer Records/

• /Library/Application Support/Avid/Audio/Plug-Ins/

• ~/Library/Preferences/Serum2Prefs.json

• ~/Library/Application Support/com.xfer.serum2/Serum2.lic

Press Cmd-Shift-G to navigate to each folder quickly.

Serum 2 User Guide 15

Exploring Serum
Serum is an incredibly versatile instrument designed for sound designers and musicians who seek
creative control over every detail of their sound. Equipped with multiple oscillators, including dedicated
noise and sub oscillators, Serum allows you to blend and shape a broad range of waveforms, from
complex wavetables to granular, spectral, and sampled sounds.

Whether you’re designing cutting-edge textures or classic synth tones, Serum offers the flexibility to
explore both familiar and experimental sonic territories with ease.

In addition, Serum features dual filters, each offering a wide selection of filter types for precise tonal
shaping. You can route oscillators through one or both filters, giving you detailed control over the
harmonic structure and timbre of your sound.

Serum Interface

Complementing this, Serum includes an array of fully-configurable envelopes and LFOs (Low Frequency
Oscillators) that you can assign to almost any control. This allows for intricate, evolving soundscapes
with dynamic changes and rhythmic modulations.

To further expand the sonic possibilities, Serum integrates a sophisticated arpeggiator and MIDI clip
system, offering advanced sequencing and performance options for live and studio use.

Taken together, the Serum interface is conveniently structured to help make sound design both easy
and intuitive.

Serum 2 User Guide 16

 Exploring Serum

Exploring Sound Design in Serum

Serum provides you with multiple ways to create and manipulate sound, enabling you to design virtually
any kind of sound you can imagine (and some you may not have thought possible).

Specifically, Serum offers you the following sound generation options, accessible through oscillators A
to C (OSC A, OSC B, and OSC C), with each offering a distinct approach to sound sculpting:

• Wavetable — Produces an evolving soundscape by cycling through or morphing between multiple

waveforms stored in a wavetable

• Multisample — Uses multiple recordings (samples) of instruments (or other sound generators)
across various notes and dynamic ranges

• Sample — Uses single samples that can be played back at different pitches, layered, looped, or
transformed with various effects

• Granular — Layers, stretches, rearranges, or modulates tiny sound fragments called grains to create
new sound textures

• Spectral — Manipulates sound by analyzing and resynthesizing the frequency spectrum, creating
new sounds with independent control over time and pitch

You can access the sound generators

using a drop-down menu.

As you read through this manual, you’ll

learn how to use each option in detail to
help craft the sounds you want.

Serum Oscillators

Serum 2 User Guide 17

Getting Started
Getting started with Serum is quick and easy. This section provides a short overview to help you
understand some common basic operations.

Adding Serum to a Track

You can add Serum to an instrument (MIDI) track in your DAW using the same procedure that you use
with any software instrument. At this point, sending MIDI notes to Serum should trigger the default
sawtooth sound.

Similarly, you should hear the sawtooth sound if you click any of the piano keys at the bottom of the
Serum user interface (UI).

Note: If you are not sure how to add an instrument to a track, refer to the documentation that came
with your DAW.

Loading a Serum Preset

Serum lets you create amazing sounds from scratch. However, a good place to start is browsing and
loading presets. To select a preset, click - Init - to display the Serum presets menu.

Serum Presets Menu

Navigate the menu to choose a preset.

After choosing a preset, you can click the < > arrows (to the right of the preset name) to navigate
through a particular preset subfolder without having to repeatedly display the presets menu.

You can also choose a preset by clicking the button (next to the main menu near the top right) to
access the presets browser.

Click an entry in the list to load the corresponding preset. Most presets load immediately; presets with
larger embedded samples, such as multisampled instruments, display a small green progress bar (directly
beneath the preset name) when loading.

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 Getting Started

Serum Presets Browser

You can preview presets to help you quickly find the right sound.

Click the (play) button to preview the

corresponding preset.

Serum plays an embedded preview clip (MIDI sequence)

if the preset designer specified one. Otherwise, Serum
plays a “fallback” clip to give you a sense of the preset. Presets Showing Play Buttons

You can choose the fallback clip from among three standard options. Serum also allows you to auto-
preview clips. See “Performing Standard Preset Operations” on page 334 for more information.

Click another play button to preview the corresponding

preset.

Click the button to stop the preview.

Preset Playing

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 Getting Started

Creating a New Sound

In addition to exploring Serum’s rich set of factory presets, you can use Serum to create your own
sounds from scratch.

If you just added Serum to a track, you will see the - Init - preset, which has a single wavetable oscillator
enabled (OSC A) together with basic envelope and LFO modulators defined. This is a perfect blank slate
from which to craft and evolve your sound.

Note: If you’ve already loaded a preset or made other changes and would like to start over, click the
main menu and choose Init Preset in the context menu.

This initializes Serum to the default

settings and sets the stage for you to
work on your new sound.

For more information about all the

options available in the main menu, see
“Appendix A: Using the Main Menu” on
page 323.

Choose Init Preset from the Main Menu

Serum 2 User Guide 20

 Getting Started

Saving Changes
After crafting a new sound or modifying an existing preset, you can save the configuration as a new
preset (that you can load later).

1. (Optional) Before saving a preset, add metadata to the preset.

a. Double-click the ARTIST field directly below the preset name and type the artist name.

b. Double-click the DESC field and add any relevant information related to the preset.

You can add any type of information that you consider helpful or informative.

Preset Metadata (Artist and Description)

2. Click the (disk) button to the left of the preset name.

Save (Disk) Button

A dialog appears allowing you to specify the file name and choose the location. Note that this file
name becomes the preset name in Serum.

3. Click the Save button.

After you’ve already saved a preset and made modifications, click the (disk) button to save
your changes. A dialog appears allowing you to type a new file name or overwrite your existing
preset file.

If you already know that you want to use the same file name (and overwrite the existing preset
file), Option-click (macOS)/Alt-click (Windows) the disk button. The preset saves using the
same file name without displaying the dialog.

Serum 2 User Guide 21

 Getting Started

Embedding Content When Saving a Preset

You can embed a wavetable or sample into
your preset when saving by clicking the
button.

After clicking, the button changes to

show that the feature is enabled.

Note: Alternatively, you can click the name of

the wavetable or sample and choose Embed
in Preset in the context menu.

In general, you should only consider

doing this if you intend to share your
preset with someone else.

Note that the option to embed a wavetable

or sample into a preset is not available for
factory-supplied content.

Embed Indicator

Dragging Audio to Your DAW

You can quickly export the last played note or chord (in
WAV format) to your DAW.

Hover over the left of the Serum logo, and drag the wave
icon that appears to an audio track in your DAW.

Exporting Audio by Dragging

Serum 2 User Guide 22

 Getting Started

Serum silently plays the note or

chord using the corresponding
pitch, velocity, and duration.

In addition to inserting the

audio on to the track, Serum also
captures the exported audio as
a WAV-format file (stored in the
Serum Presets > Renders
folder).

Dragging Audio to Your DAW

Option-click (macOS)/Alt-click (Windows) the wave icon to open the Renders folder. Shift-
drag the wave icon to copy the current (saved) preset to the macOS Finder/Windows Explorer.

Exploring Basic Operations

Serum includes a set of elements and on-screen controls designed to closely replicate the experience of
using a hardware synthesizer, while also providing all the benefits of a digital computer.

This section describes common operations when using the on-screen controls, including options
that you can use with most knobs and sliders. Subsequent chapters will describe specific options for
individual controls and other elements of the interface.

Serum 2 User Guide 23

 Getting Started

Displaying Help (Tooltips)

You can display help for any control (such as
a knob) by hovering the mouse pointer over
the control and pausing for a moment.

For example, hovering over a regular control

displays a tooltip similar to the one shown
here.

This allows you to see information about a

particular control or feature without having to
open this manual.

Important: The Help tooltips global

preference needs to be set to SHOW for
tooltips to appear. Tooltips are enabled by
default when you first install Serum.

Refer to “Exploring Global Settings” on page

312 for more information about modifying
global preferences.

Tooltip Help

Hovering the mouse pointer over a control

that has modulation assigned displays the
modulation sources.

For example, hovering the mouse over the

CUTOFF knob shows that LFO 3 and ENV 2
are assigned to modulate the filter cutoff.

Tooltip Showing Modulation Sources

Serum 2 User Guide 24

 Getting Started

Using the Serum Keyboard

Serum features an on-screen keyboard that you can use to directly play notes using your mouse, or
monitor the notes being played on an external MIDI or computer keyboard. The on-screen keyboard
also indicates which notes are being played through the Serum clip player and arpeggiator.

Serum Keyboard

You can also use the keyboard to specify basic settings including the following:

• TRANSPOSE — The number of semitones (positive or negative) to transpose all incoming and
generated MIDI notes.

• KEY — The key to use throughout Serum, most notably in the CLIP and ARP modules.

• SCALE — The scale to use. Notes outside the scale automatically conform to the selected scale.

• SWING — Use to swing or shuffle the timing of the grid in the CLIP and ARP editors.

• OSC MAPPING — Edit the note and velocity ranges of the oscillators and arpeggiator.

Using Knobs and Sliders

To adjust a knob or slider, click and drag either
up and down or left and right. A pop-up displays
the current value allowing you to dial in a specific
setting. Hold the Shift key to fine tune the
adjustment.

If your mouse has a scroll wheel, you can also use

it to adjust values up and down (without displaying
the current value in a pop-up).

Double-click a knob or slider to display a text box

showing the current value. Enter a new value for
precise adjustments.

You can change the behavior of double-

clicking a knob or slider to have Serum
reset the control to its default setting, if
you prefer.

See “Exploring Global Settings” on page

312 for more information. Click-Dragging a Knob

Serum 2 User Guide 25

 Getting Started

Right-click a knob or slider to open a context menu

that displays the settings and operations available
for that control.

You can use the menu to choose one or more

modulation sources (such as ENV 1 or LFO 2) for
the control.

You’ll read about modulating parameters later in

this guide.

You can also choose to bypass or remove a

modulator, or remove all modulators assigned to
the control.

Note: Some controls offer additional menu

options, depending on the context. You’ll learn
about these options in relevant sections of this
guide.

Right-Click Context Menu

You’ll also see the following options available on nearly all knob and slider menus:

• Reset Control — Resets the control to the default value.

This is the same as Cmd-clicking (macOS) or Ctrl-clicking (Windows) the control.

• MIDI Learn — Activates MIDI learn mode. When enabled, Serum waits for an incoming MIDI CC
value.

After Serum receives a MIDI CC value, MIDI learn mode is deactivated and the CC# is assigned to
the knob or slider. Note that the assignment is saved with the preset (patch).

• Lock Parameter — When enabled, locks the control setting (preventing a value change) when
loading presets. You can, however, continue to adjust the control manually.

The Reset Control and Lock Parameter options appear in the context menu of almost every
control in Serum.

In all cases, you can use these options to reset the control to the default value and lock a
control parameter to prevent it from changing when loading presets, respectively.

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 Getting Started

When saving a DAW session, MIDI CC assignments are saved and recalled with the
session.

When saving a preset, MIDI CC assignments are saved with the preset, but are only loaded
if the Load MIDI Map from Preset preference is enabled on the Global page (this setting is
disabled by default).

See “Preferences” on page 313 for more information about setting global preferences.

You can set the current MIDI CC assignments to load by default by choosing Save MIDI
Map in the main menu and saving the MIDI map as default.SerumMIDIMap in the
Serum 2 Presets/System/MIDI CC Maps folder.

This map then loads automatically when creating a new instance of Serum or choosing Init
Preset in the main menu. The map also automatically loads when selecting a preset if the
Load MIDI Map from Preset preference is disabled.

Undo and Redo

You can undo and redo just about any operation in Serum, encouraging you to effortlessly experiment in
your sound design.

You can access the undo and redo buttons in the Serum header, near the top right.

Undo and Redo Buttons

Click the button to undo your last operation (such as a change to a knob or an LFO shape,
among others).

Click the button to redo the last undo operation. This allows you to quickly compare and evaluate
changes to your sounds side by side.

Controlling the Main Output Volume

You can control the main output volume of Serum using the
MAIN knob (near the top right).

The stereo volume appears as a meter next to the knob.

Main Volume

Serum 2 User Guide 27

 Getting Started

Using Oscillators and Filters

Serum generates sound using a set of oscillators, powered by a range of techniques that use both
wavetables and samples. Serum then uses filters to sculpt the sound generated by the oscillators.

Each oscillator type features specific settings and parameters that you’ll read about later in this guide.
This section describes a series of operations that are common across most oscillator and filter types.

Enabling an Oscillator or Filter

You can enable an oscillator by clicking the label (containing the oscillator name and enable button).
When enabled, the button turns green.

Enabling OSC B OSC B Enabled

You can also use the power button to mute (disable) an oscillator to either solo the other oscillators or
free up CPU, as needed. Notice that when an oscillator is off, the entire panel is dimmed.

Enabling a filter is very similar, except that you need to click the power button directly.

Enabling Filter 1 Filter 1 Enabled

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 Getting Started

Choosing Oscillator or Filter Options

You can choose an oscillator or filter option using
the associated drop-down menu.

Oscillator options accessible using the drop-down

menu include wavetables, samples, multisamples,
and more.

In the case of filters, you can choose the type of

filter using the drop-down menu.

Click the < > arrows to quickly navigate to the

previous and next menu option.

Alternatively, hover over the menu and use the

mouse wheel to quickly rotate through menu
options.

Choosing a Wavetable

Using Pitch Controls

You can alter the pitch of the waveform using the
OCT (octave), SEM (semitone), FIN (fine tuning in
cents), and CRS (coarse) controls.

The CRS setting controls the pitch transpose that

tunes or detunes continuous (no snap) semitones.
CRS is most useful as a modulation destination or
automation parameter for wide sweeps.

Oscillator Pitch Controls

Serum uses separate controls for the four settings to facilitate automation and modulation (rather than a
combined value such as 36.04).

It’s often handy to assign an LFO to the octave setting, for instance, without having to count in 12
semitones.

Serum 2 User Guide 29

 Getting Started

There are times, however, when you might want to have an LFO control an oscillator pitch in a more
coarse manner (a siren-type sound might require an LFO to modulate an oscillator pitch smoothly across
an octave or more).

You can do this by modulating the CRS setting. (You’ll read about modulating controls later in this guide.)

Use the Global > Main Tuning modulation destination to have all oscillators follow a coarse
pitch change.

Setting the Octave or Semitone Mode

Serum further allows you to specify the

mode for the OCT and SEM controls.

Right-click either control and choose

the mode in the context menu.

You can select from the following

options:

• Semitones — Adjust the pitch in

semitones, which are the intervals
between two adjacent keys on
a piano tuned to 12-tone equal
temperament used in American/
European musical tradition.

This allows for fine-tuning,

transposing, or creating intervals
such as minor/major thirds, fifths,
Selecting the Mode
and more.

• Harmonics — Change the pitch by multiplying the base frequency using whole number harmonics.

This generates pitches based on the harmonic series, which is useful for creating overtone-rich
sounds, like organ tones or harmonic layers.

• Ratio — Set the pitch of the oscillator in relation to the base frequency using ratios, which is
common in FM synthesis.

In this case, the oscillator is tuned to a specific ratio relative to another oscillator to create complex
timbres. When you select this mode, you can then set the specific source (SRC) and ratio.

• Step — Adjust the pitch up or down in periods and steps, as defined by the active MTS-ESP tuning.

This option only appears when you are using microtuning and have an MTS-ESP tuning source
available.

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 Getting Started

Routing an Oscillator or Filter

You can route the signal from any oscillator (OSC A, OSC B, OSC C, SUB, and NOISE) or any filters
(FILTER 1 and FILTER 2) to a range of targets.

The following table describes the routing targets:

Target Description
Filter Route the signal to either FILTER 1, FILTER 2, or by varying degrees to both.
Main Route the signal to the main output, passing through the effects section.
Direct Route the signal to bypass the filter and effects section and play “clean”
along with the main output.
None Route the signal to no output path. You can use this setting when you
want to use an oscillator as a modulation source without having the sound
included as part of the output signal.

You can access the routing options by clicking the button near the top right of an oscillator or filter.

When you click, a set of controls

appear that are relevant to the routing
path.

For example, in the case of routing to

the Serum filters, you have the option
of routing the signal completely to
FILTER 1 (knob turned far left),
completely to FILTER 2 (knob turned
far right), or to some combination
of both (knob set somewhere in
between).

By default, OSC A is automatically

routed to FILTER 1, though FILTER 1
is not enabled in new presets.

The other oscillators and filters are

automatically routed to the Main
output. You can change the routing at
any time.
Accessing the Signal Routing Settings

Serum 2 User Guide 31

 Getting Started

You can also send the signal to the Serum busses

(BUS 1 and BUS 2) by adjusting the corresponding
knobs.

Filter Routing and Busses

To change the signal routing, click the button

and choose another option, as appropriate.

Routing Menu

Serum 2 User Guide 32

 Getting Started

Accessing the Oscillator or Filter Menu

You can use the oscillator or filter menu to
perform the most common operations related
to the module.

These operations include locking the module,

initializing the module, copying and pasting a
module (with or without modulations), and
enabling pitch tracking (in the case of oscillators).

Right-click the module label to access the

context menu.

The next sections describe the specific operations

you can perform.

Oscillator Menu
Locking a Module

You can lock a module by right-clicking the module label and choosing Lock Module in the context
menu (see the Oscillator Menu above). This causes the parameters (settings) of the oscillator module to
remain unchanged (locked) as you change presets.

For example, if you lock OSC A, the module remains the same even when you load a preset (that would
normally change the oscillator module).

After locking a module, you can unlock individual controls (such as the WT POS knob, for
example), as needed.

Note: This does not apply when you initialize the entire preset (by choosing Init Preset using the main
menu). This initializes all settings and removes any module locks that you might have set.

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 Getting Started

Initializing a Module

After making changes to an oscillator or filter, you can return the module to an initialized state without
affecting any other Serum setting.

Right-click the module label and choose Init Module in the context menu. The oscillator returns to initial
settings (including removing all modulators assigned to the module).

Copying a Module

You can copy an oscillator or filter (with or without modulations) and paste it to another (similar) module.
This works when copying and pasting modules in the same preset, as well as when you want to copy
and paste between presets.

For example, consider the case where you configure an oscillator module with specific wavetable,
unison, detune, and warp settings. In addition, you have LFO 1 modulating the wavetable position
(WT POS knob).

Right-clicking the oscillator label and choosing Copy in the menu copies the module to Serum’s
internal clipboard. Right-clicking another oscillator module and choosing Paste in the menu pastes the
configuration (all settings except the WT POS modulation) to the corresponding module.

To copy and paste a module configuration including modulations, right-click the oscillator label and
choose Copy (w/mods) in the menu. Pasting to a new module now includes the WT POS modulation
from the earlier example.

As mentioned, this copy and paste operation works even after changing or initializing a preset. In
addition, the module configuration stays on Serum’s internal clipboard after pasting, allowing you to
quickly paste the same configuration to multiple modules as needed. It is not possible, however, to copy
a module from one instance of Serum to another.

Hold the Option/Alt key and drag the module label (next to the power button) to another
(similar) module to copy the module without modulations.

Hold the Shift-Option or Shift-Alt keys and drag the module label to another module to copy
with modulations.

Dragging from one module label to another without any keyboard modifiers swaps the two
modules (including modulation assignments).

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 Getting Started

Enabling Pitch Tracking

Pitch tracking instructs the oscillator to adjust its pitch in response to the MIDI note or key being
played. This ensures that the oscillator’s frequency corresponds to the desired musical pitch. Pitch
tracking is typically used with melodic and harmonic sounds, where the pitch needs to follow the
keyboard.

Pitch tracking is enabled by default.

You can choose to disable pitch tracking by right-clicking the oscillator label and toggling Enable Pitch
Tracking off in the context menu.

You might choose to disable pitch tracking with the following types of sounds:

• Drones or static sounds

This produces a constant, unchanging pitch regardless of the notes played. This is common with
ambient soundscapes that don’t need pitch variation. This is also useful for layering a static tonal
element beneath a dynamic lead or pad.

• Percussive sounds

These sounds often don’t rely on pitch tracking since their character is defined more by their
transient and timbral qualities than specific pitch. You can use this with a variety of drum sounds,
such as kick drums, snares, or hi-hats, as well as metallic or inharmonic percussive textures.

• Noise-based effects

Noise signals (white, pink, or custom noise) aren’t inherently pitched, so pitch tracking is irrelevant.
You can also use this with wind, rain, or static effects, in addition to risers, sweeps, and impacts.

• Experimental sounds

Disabling pitch tracking can lead to unexpected and unique sonic results. This can be helpful for
creating unconventional or dissonant sounds. This can more easily allow you to explore textures
where the focus is on timbre and modulation rather than pitch accuracy.

You can also disable pitch tracking to add layers without harmonic conflicts. A non-pitch-tracked
oscillator can add texture or depth without interfering with the harmonic structure (such as a static sub-
bass tone underneath a harmonic element).

When pitch tracking is disabled, the Multisample, Sample, Granular, and Spectral
oscillators play C3 (MIDI note 60), whereas the Wavetable oscillator plays C-2
(MIDI note 0), allowing it to be used as an LFO.

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 Getting Started

Pitch Bend Tracking

Pitch bend tracking determines whether MIDI

pitch bend affects the frequency of an oscillator
when pitch tracking is disabled.

The option appears on the Oscillator context menu

only when Enable Pitch Tracking is disabled, and is
only available for Sample, Granular, and Spectral
oscillator types. Pitch bend tracking is enabled by
default.

You might choose to disable pitch bend tracking

for static, drone, or noise-based sounds so that
they remain at a constant pitch, even when moving
the pitch bend wheel.

Note that Wavetable and Multisample oscillator

types always track pitch bend when pitch tracking
is disabled.

Pitch Bend Tracking Enabled

Resizing the UI
You can resize the Serum user interface to make it fit appropriately
within your work environment.

The easiest way to resize the interface is to click and drag the lower
right corner of the UI (similar to how you would resize most other
windows using your computer).

For more precise control, click the Serum 2 logo (near the top left)
and choose a resize option in the menu that appears. The window
resizes to match your selection.

After resizing, you can make this size the default setting by clicking
the Serum 2 logo again and choosing Set x% as Default, where x is
the current setting.

To return to the default setting of 100%, click the Serum 2 logo and
choose Default (100%) using the menu.

Resize Menu

Serum 2 User Guide 36

Using Wavetable Oscillators
As with the original Serum, wavetable oscillators remain at the heart of sound generation in Serum 2.
Unlike many wavetable synthesizers, however, Serum tables are multi-cycle, offering a greater variety of
sounds.

Serum oscillator playback has been carefully constructed to give you a high-frequency representation to
the limits of the human ear, without the audible aliasing artifacts (Nyquist reflection) commonly found
on most wavetable synthesizers.

While this requires more CPU during both load and run-time, Serum’s advanced SSE (Streaming SIMD
Extensions) optimizations effectively help to minimize the CPU expense. We think you’ll agree that the
benefits in sound purity make it worthwhile.

Oscillator Panel (with 2D Waveform)

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 Using Wavetable Oscillators

What is a Wavetable?
A wavetable is a small amount of digital audio (sample data or waveform) that is played back in a looping
fashion.

The frequency (pitch) of the resulting note is determined by the rate (the speed between the repeats)
at which the waveform is played. The tone (timbre and harmonics) of the sound is determined by the
content of the waveform.

Anatomy of a Serum Wavetable

Wavetables in Serum consist of up to 256 subtables, or single-cycle waves (referred to hereafter as
frames). You can think of this as (up to) 256 discrete waveforms joined together end-to-end in the
parent file on disk.

In normal circumstances, you can hear one of

these 256 frames at a time. However, if you assign
automation to the WT POS knob, the sound
starts to glide through the various frames, thereby
becoming animated.

The wavetable in the illustration contains six

frames, with yellow highlighting the current frame
and green showing the five other frames.

If you increase the number of unison voices and

turn up the unison WT POS control (in the unison
settings), you’ll hear multiple frames (subtables) Wavetable Frames
playing back simultaneously.

Strictly speaking, when Serum loads a wavetable, it uses 2048 samples for a frame
(subtable) of the wavetable set. This means that the maximum file size is 2048 (samples) x
256 (frames) x 32 (bits), which is exactly 2 megabytes.

However, most wavetable files will not be this large. A good sounding wavetable can consist
of just a few frames. The remaining frames can be interpolated (in the Wavetable Editor) to
allow for smooth-sounding transitions.

These interpolated frames are generated through crossfading (mix blend) or spectral
morphing (frequency + phase blend). These frames are computed at load time; Serum
embeds the interpolation type rather than the interpolated waveforms (reducing disk
space).

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 Using Wavetable Oscillators

Using Wavetables
Serum features three multi-purpose oscillator
modules, as well as dedicated NOISE and SUB
oscillators (discussed separately later).

You can use any or all of the three oscillators in

wavetable mode, taking advantage of advanced
display and editing capabilities to help you get the
greatest sonic possibilities.

This section describes how to use wavetables in

Serum.

OSC A in 2D View

Exploring the Waveform Display

OSC A, OSC B, and OSC C all display a green
waveform area with two viewing options: 2D and
3D.

Clicking on the waveform toggles between the

two views.

In 2D mode, you see a single-cycle (frame) of the

selected wavetable. You can use this view to see
the warp feature in real-time (described later in
this chapter).

The 3D view, in contrast, displays all frames

(subtables) at-a-glance, with each frame
represented by a green horizontal waveform,
interpolated frames in gray, and the currently-
selected frame in yellow.

Notice that the current frame number (wavetable

position) appears in the lower left of the waveform
area. OSC A in 3D View (with wavetable position
number)

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 Using Wavetable Oscillators

Choosing a New Wavetable

You can load a new wavetable by clicking the drop-

down menu and choosing an option.

Click the < > arrows to quickly navigate to the

previous and next wavetable respectively.

Alternatively, hover over the menu and use the

mouse wheel to quickly rotate through wavetable
options.

Choosing a Wavetable

Editing a Waveform

You can take a closer look at a wavetable by hovering over the top-right corner of the waveform display
and clicking the button.

Note that the button is initially dimmed until

you hover directly over it.

Doing so opens the Wavetable Editor, presenting

you with a rich set of tools to modify and
manipulate the wavetable in multiple ways.

Click the button to close the Wavetable

Editor.

You’ll learn all about the Wavetable Editor and its

many features in “Using the Wavetable Editor” on
page 274.

Wavetable Editor Button

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Wavetable Editor

Phase
Use the PHASE control to specify where the
oscillator begins playing back when a note is
triggered.

It is the same concept as sample start on a sampler

(except the “sample” is a very small waveform).

Since oscillators tend to be reasonably high

frequency, you may not notice a difference when
changing this knob.

In particular, if the adjacent RAND control is up

considerably, you probably won’t hear a difference
when adjusting the phase (because RAND alters
the phase on each new note).

Oscillator Phase Control

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Having said that, the effect can be very pronounced in the following scenarios:

• With a smooth waveform and fast-attack envelope

If your wavetable is a sine wave, for instance, and the ENV 1 attack is very fast (set to a small
value), you will hear a click at the beginning of the sound if the PHASE control is set to a non-zero
crossing (0% or 50% represent the zero crossings in a default sine wave).

• Using two or more oscillators with the RAND setting off

The interaction between two or more oscillators can be very noticeable due to phase cancellation.
Adjusting the start time of one of the oscillators results in a different tone.

If the oscillator waveform display is in 2D (single table view), moving the PHASE control causes a
yellow line to appear indicating where the note onset will occur.

Randomizing the Phase

Use the RAND (random) control to alter the PHASE knob value by a random amount for each new
voice.

You might want to randomize the start phase of an

oscillator for the following reasons:

• To provide a different start or click/thump to

each note

• To provide a random tone to each note (when

layering multiple oscillators), as the phase
cancellation between the oscillators varies
with each new note

• To reduce or remove the “laser zap” effect

when unison (slightly detuned) notes are
triggered

Oscillator Random Control

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For example, do the following to hear the effects of the RAND control:

1. Set PHASE to 0 degrees.

2. Set RAND to 0 percent.

3. Raise the UNISON number to a high value, such as 8.

4. Lower the DETUNE slightly, for instance, to 10 o’clock (a value of 0.10).

At this point, you should hear a “laser zap” phasing sound resulting from the unison oscillators all
starting together in phase, and slowly drifting apart from their detune.

Every time you trigger the note, you’ll hear the same laser zap sound since the voice phases are
restarting. While this can sometimes be cool, generally this is undesirable as the sweeping sound can be
distracting.

As you raise the RAND control, notice how the effect becomes less pronounced as a random phase
offset is introduced into each voice separately. By the time you reach 100% using the RAND control,
you will no longer hear the “zap” sound.

Phase Legato

In the case of the “laser zap” phasing sound produced in the previous section, the default behavior is
that when Legato is disabled (in the VOICING section) and a voice is stolen, the wavetable oscillator
phase does not reset at note on. Therefore, you won’t hear that “laser zap”.

Also, in cases when Legato is enabled and Serum is playing polyphonically (including when not stealing
a voice), the wavetable oscillator phase does reset at note on. This results in you hearing the zap even
though legato is enabled and you want a smooth transition between notes.

The default behavior is how Serum 1 works, and is intended to avoid clicks at note on, which would be
particularly evident with a simple sine wave.

However, with the above settings, we want the opposite behavior. You can toggle this by right-clicking
the PHASE control and choose Phase Legato in the context menu.

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Setting Phase Memory

You can set the phase memory for the wavetable using the phase memory drop-down menu. The phase
memory specifies how phase and phase randomization should be determined for new notes.

Phase Memory Menu

The following table describes the options:

Option Description

All Voices New notes use the PHASE and RAND control settings for all voices. This is
the default setting.
Contiguous New notes continue with the phase of the previous note.
Per Voice New notes start with the same editable phase each time.

If you set phase memory to Per Voice while one or more notes are sounding, Serum captures
the current phase from the most-recently sounded note.

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Wavetable Position
Use the WT POS knob to set the position within
the wavetable. In other words, the knob selects
the frame (subtable) that is currently audible.

Setting the WT POS knob to the minimum setting

of 1 selects the first frame (highlighted in yellow).

Remember, yellow always indicates the currently-

selected (audible) frame.

Right-click the WT POS knob and choose Smooth

Interpretation in the menu to allow smoother
waveform transitions without being destructive.

This helps keep the wavetable intact while

morphing smoothly between positions.

Oscillator WT POS Control

Unison
Use the UNISON control to set the number of unison voices, effectively “stacking” oscillators in a way
that is similar to playing multiple notes of the same pitch, but slightly detuned.

Click the field and drag to set the appropriate

value. You can also double-click the field and type
a value.

Serum allows you to stack up to 16 voices in

unison, but doing so can result in a more “cloudy”
sound and less like distinct voices. The classic
magic number for unison is 7.

Serum has a special capability that keeps the level

increase in check as you increase the number of
unison voices, effectively maintaining the volume
at the same level.

Note: Unison causes Serum to generate multiple

voices, raising CPU usage. The color of the
UNISON field changes as you increase the
number of unison voices as a reminder of the CPU
consumption.

Wavetable Unison Control

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Click the button to display the unison

settings.

The wavetable unison settings appear.

Wavetable Unison Settings

You can specify the following settings:

Setting Description

MODE The detune mode, from among the following:

• Linear — The detuning between each additional voice increases in a

consistent, linear fashion. This means that the pitch of each voice is
spaced evenly in terms of frequency, creating a smooth spread that
retains an even distribution.

This mode can sound very controlled and smooth, giving a thick and
coherent texture.

• Super — Multiple voices are slightly detuned from each other but with
a special emphasis on creating a dense and powerful sound, often with
a slight stereo spread.

Use this mode to create a lush, wide sound, especially with supersaw
sounds, where the detuned voices give a rich, full sonic character.

• Exp — The detuning between voices increases exponentially as

you move away from the central pitch. This means that the spacing
between voices gets wider more quickly as you move outward,
creating a more dramatic spread compared to linear.

This mode can create unique, rich textures, especially for sounds that
need to be more aggressive or have a strong presence in a mix.

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Setting Description

MODE (cont.) • Inv — The detuning behavior is inverted, with lower voices detuned
more sharply compared to higher ones.

Use this mode to create interesting phasing effects or to produce

sounds with a less conventional detuning profile.

• Random — Introduces a random element to the detuning of each

voice. Instead of being evenly spaced, the voices are detuned
unpredictably.

This can create a more organic or chaotic sound, ideal for achieving
textures that are less polished and more natural or experimental.

STACK The unison stacking, which instructs Serum to not just duplicate the unison
voices at the same pitch but instead transpose or harmonically adjust the
voices.

You can choose from among the following options:

• Off — Do not stack the unison voices

• 12 (1-3x) — Distribute voices between the original pitch and octave

transpositions, with a range 1-3 octaves higher

• 12+7 (1-3x) — Distribute voices between the original pitch, fifth, and
octave transpositions, with a range 1-3 octaves higher

• Center-12 — Transpose the center voices down one octave

• Center-24 — Transpose the center voices down two octaves

WIDTH The extent to which the unison voices are spread out across the stereo
field, determining how wide or narrow the resulting sound feels in a stereo
mix.

When you increase the width parameter, the unison voices are spread
farther apart in the stereo spectrum, placing some voices more to the left
and others more to the right. This creates a sense of space and a wider,
more immersive sound.

Conversely, decreasing the width narrows the stereo spread, making the
sound more centered and focused. This can be useful for sounds that need
to be more direct or fit better in a dense mix without dominating the stereo
field.

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Setting Description

RANGE The extent or range of detuning applied to the unison voices, determining
how far apart in pitch the individual voices are spread around the central
frequency of the original sound.

When the range is set to a low value, the detuning between the unison
voices is minimal. The voices remain relatively close in pitch to the original
frequency, creating a subtle and smooth chorusing effect. This can add
warmth and a slight thickness to the sound without drastically changing its
character.

When the range is increased, the detuning becomes more pronounced,

and the unison voices are spread further apart in pitch. This creates a more
dramatic and sometimes more chaotic or dissonant effect, which can be
useful for creating lush, wide textures or aggressive, detuned leads.
WT POS The wavetable frame that the unison voice plays at a particular moment.
By modulating this position, you can morph through different waveforms,
creating dynamic, evolving sounds.
WARP 1 Spread out the warp amount applied to each voice around the current
WARP 1 knob position.
WARP 2 Spread out the warp amount applied to each voice around the current
WARP 2 knob position.

You can further adjust the unison setting using the DETUNE and BLEND knobs.

Unison Detune

Use the DETUNE knob to specify the tuning offset +/- for the additional voices. This is only applicable
when unison is enabled (set to a value above 1).

Unison Blend

Use the BLEND knob to specify the level offset of the unison voices versus the “central” unison voice or
voices (1 if unison is set to an odd number of voices and 2 if set to an even number).

You can think of BLEND as a wet/dry mix between a unison (wet) and non-unison (dry) sound. The
default value of 75% is an even blend between all the voices. Note that this is only applicable when the
number of unison voices is greater than two.

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Warp
Setting the warp allows you to manipulate the
playback (and sound) of the wavetable oscillator.

By default, warp is set to OFF (as displayed next

to the corresponding knob). Clicking the current
setting displays a menu from which you can
choose from among the available warp modes.

You can also use the < > arrows to conveniently

switch between different warp modes without
having to open the menu. After selecting a mode,
you can use the corresponding knob to set the
depth.

Note that if the waveform is in 2D view (with a

single frame visible), you can see how the warp
mode affects the waveform for Sync, Alt Warp,
and Distortion modes.

Wavetable Warp Control

Exploring the Warp Modes

Serum offers an extensive set of warp modes.

As with many parts of Serum, the best way to

learn about them is through experimentation.

Wavetable Warp Menu

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The following table describes the available warp modes:

Category Warp Mode Description

Off The warp function is turned off.

Sync Synchronize wavetable playback to an internal oscillator that
restarts in sync with the original oscillator phase.
The warp control sets the pitch of the internal oscillator; when
increased, the harmonic content shifts upwards while retaining
the pitch of the original oscillator.
This can create a harmonious effect when the original and
internal oscillator relate by a whole-number ratio (1:2, 1:5, and
so on). Pitches outside of these values can cause a saw-wave
to form at the end of each cycle.

When you select Sync mode, a WARP Var fader control

appears directly below the menu. Use this to adjust the
smoothness of the sync from traditional “hard sync” to a
very soft “soft sync.”
Alt Warp Bend + Pinch (bend) the waveform inwards (towards the middle of the
wave cycle).
Bend - Pull (bend) the waveform outward (towards the edges of the
wave cycle).
Bend +/- Allow for both of the above, depending on WARP knob value.
A setting of 12 o’clock on the WARP knob (50%) represents
no change to the sound.
PWM Push the entire waveform to the left. This is useful with square
wave type sounds, especially for the classic PWM sound (but
useful with other waveforms as well).
Asym + Similar to Bend, but in this case bend the entire waveform to
the right instead of both halves of the duty cycle separately.
Asym - Bend the entire waveform to the left.
Asym +/- Bend the entire waveform to the left or right.
Flip Create an instantaneous polarity flip (often called phase
inversion) on the waveform. The WARP knob determines
where in the duty cycle the flip occurs.

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Category Warp Mode Description

Alt Warp Mirror Create a mirror-image of the waveform for the second half of
(cont.) the duty cycle.
This has an “octaved” type of quality to the sound due to the
doubling of the waveform into both halves of the wave cycle.
For this setting, the WARP knob behaves similarly to the Asym
+/- mode, except on both halves independently.
Due to the mirroring of the waveform, this mode always has
an audible effect.
Remap 1 Custom remapping of the wave cycle. When you select this
option, a pencil button appears that you can use to open a
graph showing the way your waveform will remap.
A diagonal line from bottom-left to top-right indicates no
change to the waveform (y=x). The WARP knob determines
the strength of the remap, from 0 (y=x) to 100% (what you see
on the graph).
Remap 2 Represents mirrored remapping.
This is the same as Remap 1 but applies the graph to each
half the waveform independently. This allows for symmetric
remapping without the need to draw symmetric shapes on the
graph.
Remap 3 Represents sinusoidal remapping.
This is another remapping option that saves you from having
to draw fancy curves.
Remap 4 Represents a 4x remapping.
This is similar to Remap 2 (mirrored) but in this case the graph
applies four times. This creates a more busy sound, and can be
helpful when you want something nasty.
Quantize Similar to sample-and-hold, that is, a sample rate reduction.
Compared to an SR Redux effect, this applies to the waveform
itself.
This causes the aliasing sound to follow the pitch perfectly
(instead of having that “same ringing pitch on all notes” quality
that a redux effect creates).
Odd/Even Proportionally vertically scale the waveform. Use this to emit
only the odd or even harmonics from the signal or a mixture of
the two.
At 50%, you have the original signal. At 0%, you hear only the
odd harmonics. At 100%, you hear only the even harmonics
(which creates an octaving effect since the first harmonic is
missing).

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Category Warp Mode Description

Filter LPF Apply a low pass filter.

HPF Apply a high pass filter.
Distortion Tube Emulate the characteristics of analog tube amplification.
The signal is subjected to nonlinearities that mimic the
behavior of vacuum tubes, producing a warm, harmonically
rich, and often smooth-sounding distortion.
Soft Clip Apply gentle, nonlinear compression to the signal, creating a
smoother, less aggressive distortion compared to hard clipping.
Use this to add warmth and character to a sound without
introducing harsh or unpleasant artifacts.
Hard Clip Create a type of distortion that aggressively limits the signal
by abruptly cutting off its peaks after it exceeds a certain
threshold.
This results in a sharp, harsh form of distortion that creates a
more aggressive and intense sound compared to softer forms
of clipping.
Diode 1 Create a type of distortion that emulates the sound
characteristics of analog diode clipping circuits, often found in
classic guitar pedals and analog equipment.
This mode adds a unique type of distortion that is both warm
and aggressive, with specific tonal characteristics derived from
the behavior of diodes in the signal path.
Diode 2 Apply a sinusoidal transfer curve with increased hard clipping
as drive is increased.
Linear Fold Create a type of wavefolding distortion that produces
a distinctive and often aggressive sound by folding the
waveform back on itself whenever it exceeds a certain
amplitude threshold.
This folding effect adds rich harmonic content and introduces
a complex, metallic, or harsh character to the sound.
Sine Fold Create a type of wavefolding distortion effect that shapes the
input waveform using a sine-based folding process.
This effect introduces complex harmonic content and adds a
smooth but dynamic character to the sound, often resulting in
rich, evolving timbres that can range from warm and musical to
intense and aggressive.

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Category Warp Mode Description

Distortion Zero-Square Modify the waveform in such a way that any part of the signal
(cont.) below a certain amplitude threshold is forced to zero, while
parts of the waveform above the threshold are squared or
otherwise drastically altered.
This creates a sharp, abrupt change in the shape of the
waveform, leading to a sound that is both harsh and
harmonically rich.
Asym Create an asymmetric effect that applies different distortion
characteristics to the positive and negative halves of an audio
waveform.
This type of waveshaping introduces a unique harmonic profile
by treating one side of the waveform differently from the
other, resulting in a sound that can range from subtle warmth
to highly complex and rich overtones.
Rectify Create a type of waveshaping effect that modifies the signal
by altering or “rectifying” the waveform, typically by flipping or
removing one half of the waveform.
This creates a distinct, harmonically rich, and sometimes harsh
or metallic sound, often associated with aggressive or synthetic
timbres.
Sine Shaper Create a type of waveshaping distortion that shapes the audio
signal using a sine function.
This type of distortion applies a nonlinear transformation
to the input signal, resulting in a smoother, more rounded
distortion that introduces harmonics in a musical and often
warm manner.
Stomp Box Create a distortion effect that emulates the sound of classic
distortion or overdrive pedals used by guitarists (stomp boxes).
This effect reproduces the gritty, crunchy, and saturated tones
characteristic of analog guitar pedals, bringing warmth, edge,
and intensity to a wide range of sounds.
Tape Sat. Create a distortion effect that emulates the warm, rich sound
characteristics of analog tape recording.
Tape saturation is a form of soft-clipping distortion that occurs
naturally when audio signals are recorded to magnetic tape,
especially at higher levels.
This effect is highly valued for its ability to add warmth,
harmonic richness, and a sense of vintage character to an
audio signal.

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Category Warp Mode Description

Distortion Soft Sat. Create a distortion effect that introduces subtle, smooth,
(cont.) and musical saturation to the signal. It is designed to gently
enhance the harmonic content of the sound without
introducing harsh or aggressive distortion.
Soft saturation is often used to add warmth, fullness, and a
natural, analog-like character to audio, making it a popular
choice for enhancing digital recordings.
FM FM (from other Perform frequency modulation using the other oscillator or
oscillator) filter.
For example, FM The other oscillator or filter must be enabled for this to work,
(B) however, you can turn down the volume of the other oscillator
if you want to use the other oscillator simply as a modulation
FM (from other
source.
oscillator)
For example, FM
(C)
FM (Noise)
FM (Sub)
FM (Filter 1)
FM (Filter 2)
Thru-Zero Cause the carrier oscillator (the one producing the sound)
to continue to oscillate correctly even when its frequency is
modulated into negative values by the modulator oscillator.
Normally, if the modulation drives the carrier oscillator’s
frequency below zero, it either clamps at zero (stops
oscillating) or reflects back to a positive value (causing a
discontinuity).
With Thru-Zero, when the frequency modulation drives the
carrier frequency below zero, the carrier oscillator doesn’t stop
or reflect; instead, it inverts its phase and continues oscillating.
This allows for smooth and continuous modulation, resulting in
a more natural and harmonically rich sound.
The inversion of phase (caused by negative frequencies) adds
new harmonic characteristics, making Thru-Zero especially
useful for lush, metallic, or bell-like tones.

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Category Warp Mode Description

FM (cont.) Exp Use an exponential scaling curve. This means small changes
in the modulator’s amplitude can cause dramatic changes
in the carrier frequency, especially as the modulation depth
increases.
Compared to linear FM, exponential FM produces a broader
and more pronounced harmonic spectrum. It is often described
as brighter or harsher due to the rapid frequency sweeps
caused by the exponential relationship.
Linear Use a linear scaling curve. This means that the modulation
source (modulator oscillator) affects the frequency of the
carrier oscillator in a direct, proportional manner.
This ensures that the carrier oscillator maintains its overall
pitch, even when modulated heavily. This makes it particularly
useful in musical contexts, as it allows for predictable harmonic
and inharmonic spectra without drastically detuning the base
pitch.
Linear is often described as smooth, clean, and more “musical”
compared to other FM types such as exponential FM. This
makes it great for bell-like tones, pads, and other complex but
stable timbres.
Note that linear FM is thru-zero but with a clamp at zero. This
allows you to do the traditional “can’t do thru-zero” FM.
PD PD (from other Perform phase distortion using the other oscillator or filter.
oscillator)
The other oscillator or filter must be enabled for this to work,
For example, PD however, you can turn down the volume of the other oscillator
(B) if you want to use the other oscillator simply as a modulation
source.
PD (from other
oscillator) This is similar to FM except that the phase is modulated
instead of the frequency.
For example, PD
(C)
PD (Noise)
PD (Sub)
PD (Filter 1)
PD (Filter 2)
PD (Self)

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Category Warp Mode Description

AM AM (from other Perform amplitude modulation using the other oscillator or

oscillator) filter.
For example, AM The other oscillator or filter must be enabled for this to work,
(B) however, you can turn down the volume of the other oscillator
if you want to use the other oscillator simply as a modulation
AM (from other
source.
oscillator)
This is similar to FM except that the amplitude is modulated
For example, AM
instead of the frequency.
(C)
AM (Noise)
AM (Sub)
AM (Filter 1)
AM (Filter 2)
RM RM (from other Perform ring modulation using the other oscillator or filter.
oscillator)
The other oscillator or filter must be enabled for this to work,
For example, RM however, you can turn down the volume of the other oscillator
(B) if you want to use the other oscillator simply as a modulation
source.
RM (from other
oscillator)
For example, RM
(C)
RM (Noise)
RM (Sub)
RM (Filter 1)
RM (Filter 2)
Swap Warps Swap the WARP 1 mode (on the left) with WARP 2 mode (on
the right).

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Pan
Use the PAN knob to control the placement of the
waveform in the stereo field (left to right).

Wavetable Pan Control

Level
Use the LEVEL knob to control the output volume
of the oscillator.

Wavetable Level Control

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Using Multisample Instruments
Serum features the ability to set any of the oscillators to function as a multisample instrument that
utilizes an array of samples—recordings of an actual instrument—played across a range of pitches,
intensities, and articulations.

With a multisample instrument, individual notes are recorded at different velocities (soft to loud) and
sometimes with various playing techniques, such as plucking, bowing, or using different mallets.

When using a multisample instrument, Serum accurately selects the appropriate sample based on the
MIDI input—evaluating both the pitch and velocity of the note—ensuring that the output sound mimics
the real instrument’s response as closely as possible. For example, playing softly might trigger a sample
of a gently played note, while pressing hard would trigger a sample of the same note played with force.

Layering multiple distinct samples achieves the effect of rich, lifelike audio textures that respond
accurately to different playing styles. This can capture the nuanced tonal variations and expressive
characteristics of the original instrument, allowing for a highly realistic and responsive musical
experience.

Selecting a Multisample Instrument

Using OSC A, OSC B, or OSC C, click the header
and choose Multisample in the menu that
appears.

Multisample in the Oscillator Menu

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The oscillator switches to multisample mode.

Initially, the waveform display is empty since no

instrument has been loaded.

Multisample Instrument

Click the drop-down menu and choose a

multisample instrument.

You can also load a multisample instrument using

a .sfz file. Using the menu, choose Load SFZ and
select the file using the dialog that appears.

SFZ files are text-based files that describe how

audio samples (such as WAV files) should be
played by a sampler.

The files map audio samples to specific notes,

velocities, or other MIDI parameters. SFZ files can
also include instructions for dynamic layers, key
switches, round robins, and other articulations.

Furthermore, Serum supports SFZ envelope

parameters to help shape the sound.

Serum does not natively support

SoundFont 2 (SF2) files. There are, Multisample Instrument Menu
however, multiple open source
applications that can convert files from
SF2 to SFZ file formats.

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After loading an instrument, the display shows the

multisamples that comprise the instrument.

Playing a note highlights the specific sample,

representing the corresponding pitch and velocity.

Multisample Instrument Loaded

Clicking in the display displays the waveform of

the last note played.

Multisample Instrument (Note Played)

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Setting the Multisample Envelope

You can modify the envelope by clicking the button. The envelope pane appears, initially disabled.

SFZ files contain envelope information for

playback. This can be per note, per group, or
global.

Click the OVERRIDE button to activate the

envelope display and override the envelope
configuration from the SFZ file.

Use the knobs to adjust the envelope shape.

Multisample Envelope Pane

The following table describes the available controls:

Knob Description

DELAY The time (in milliseconds) before the envelope begins after a note is
triggered, allowing you to introduce a pause before the attack phase starts.
This is useful for creating rhythmic effects or gradual sound layering, giving
more control over how and when the envelope affects the sound.
Right-click the DELAY knob and choose BPM Sync in the context menu to
synchronize the delay with the musical tempo. When selected, you can set
the delay in beats and bars.
A (Attack) The time it takes for the sound to reach its maximum level after a note is
triggered. This shapes the initial onset of the sound, allowing for smooth
fades or sharp, immediate beginnings depending on the setting.
H (Hold) The amount of time the sound remains at its peak level after the attack
phase is completed.
This allows the sound to sustain momentarily before moving into the decay
phase, adding emphasis and length to the peak of the sound.
D (Decay) The time it takes for the sound to transition from its maximum level after the
attack phase to the sustain level.
This shapes the gradual reduction in volume, allowing you to create more
natural fades or sharp drops in sound intensity depending on the setting.

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Knob Description

S (Sustain) The steady level the sound maintains after the decay phase, as long as the
note is held.
Unlike other stages, the sustain level lasts indefinitely until the note
is released, allowing for either continuous sound or a softer presence
depending on the setting.
R (Release) The time it takes for the sound to fade out after the note is released.
This shapes the tail of the sound, allowing for smooth, gradual decays or
quick cutoffs depending on the chosen release time.

You can also adjust the envelope by clicking and dragging each point directly on the graph. The cursor
changes to indicate whether the point can be moved horizontally or freely in all directions, providing
visual feedback for precise control.

Velocity Track
Use the VEL TRACK control to adjust the sensitivity of the note velocity. After enabling velocity
tracking, click and drag in the field to modify the setting.

Random
Use the RAND control to randomize the initial phase of the sample. This is similar to the random setting
for other oscillator modes. Click and drag in the field to modify the value.

Setting Multisample Parameters

You can set the timbre, unison (including detune
and blend), and adjust the waveform warp for the
multisample instrument.

You can also adjust the pan and level of the signal.

Multisample Parameters

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Timbre
Use the TIMBRE knob to adjust the multisample timbre.

For multisamples with zone mapping, this control inversely adjusts mapped samples to pitch. This alters
how the samples respond to changes in pitch across different key zones.

Normally, as you play higher notes, the pitch of the sample increases, and as you play lower notes, it
decreases. When you inversely adjust the mapped samples to pitch, the opposite happens: higher notes
trigger samples that are mapped to lower pitches, and lower notes trigger samples mapped to higher
pitches.

This creates an unusual or experimental timbral effect, as the relationship between pitch and sample
playback is reversed, potentially adding unique tonal qualities to the sound.

Unison
Use the UNISON control to set the number of unison voices, effectively “stacking” oscillators in a way
that is similar to playing multiple notes of the same pitch, but slightly detuned.

Click the field and drag to set the appropriate value. You can also double-click the field and type a value.

This is similar to the unison setting for other oscillator modes.

Note: Unison causes Serum to generate multiple

voices, raising CPU usage. The color of the
UNISON field changes as you increase the
number of unison voices as a reminder of the CPU
consumption.

Click the button to display the unison

settings.

Multisample Unison Settings

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You can specify the following settings:

Setting Description

MODE Set the detune mode, from among the following:

• Linear — The detuning between each additional voice increases in a

consistent, linear fashion. This means that the pitch of each voice is
spaced evenly in terms of frequency, creating a smooth spread that
retains an even distribution.

This mode can sound very controlled and smooth, giving a thick and
coherent texture.
• Super — Multiple voices are slightly detuned from each other but with a
special emphasis on creating a dense and powerful sound, often with a
slight stereo spread.

Use this mode to create a lush, wide sound, especially with supersaw
sounds, where the detuned voices give a rich, full sonic character.
• Exp — The detuning between voices increases exponentially as
you move away from the central pitch. This means that the spacing
between voices gets wider more quickly as you move outward, creating
a more dramatic spread compared to linear.

This mode can create unique, rich textures, especially for sounds that
need to be more aggressive or have a strong presence in a mix.
• Inv — The detuning behavior is inverted, with lower voices detuned
more sharply compared to higher ones.

Use this mode to create interesting phasing effects or to produce

sounds with a less conventional detuning profile.
• Random — Introduces a random element to the detuning of each voice.
Instead of being evenly spaced, the voices are detuned unpredictably.

This can create a more organic or chaotic sound, ideal for achieving
textures that are less polished and more natural or experimental.
STACK Set the unison stacking.

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Setting Description

WIDTH The extent to which the unison voices are spread out across the stereo field,
determining how wide or narrow the resulting sound feels in a stereo mix.

When you increase the width parameter, the unison voices are spread
farther apart in the stereo spectrum, placing some voices more to the left
and others more to the right. This creates a sense of space and a wider,
more immersive sound.

Conversely, decreasing the width narrows the stereo spread, making the
sound more centered and focused. This can be useful for sounds that need
to be more direct or fit better in a dense mix without dominating the stereo
field.
RANGE The extent or range of detuning applied to the unison voices, determining
how far apart in pitch the individual voices are spread around the central
frequency of the original sound.

When the range is set to a low value, the detuning between the unison
voices is minimal. The voices remain relatively close in pitch to the original
frequency, creating a subtle and smooth chorusing effect. This can add
warmth and a slight thickness to the sound without drastically changing its
character.

When the range is increased, the detuning becomes more pronounced,

and the unison voices are spread further apart in pitch. This creates a more
dramatic and sometimes more chaotic or dissonant effect, which can be
useful for creating lush, wide textures or aggressive, detuned leads.
WARP 1 Spread out the warp amount applied to each voice around the current
WARP 1 knob position.
WARP 2 Spread out the warp amount applied to each voice around the current
WARP 2 knob position.

You can further adjust the unison setting using the DETUNE and BLEND knobs.

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Unison Detune

Use the DETUNE knob to specify the tuning offset +/- for the additional voices. This is only applicable
when unison is enabled (set to a value above 1).

Unison Blend

Use the BLEND knob to specify the level offset of the unison voices versus the “central” unison voice or
voices (1 if an odd number, 2 if an even number of unison).

You can think of BLEND as a wet/dry mix between a unison (wet) and non-unison (dry) sound. The
default value of 75% is an even blend between all the voices. Note that this is only applicable when the
number of unison voices is greater than two.

Warp
Setting the warp allows you to manipulate the playback/sound of the wavetable oscillator.

By default, warp is set to OFF (as displayed next to the corresponding knob). Clicking the current setting
displays a menu from which you can choose from among the available warp modes.

You can also use the < > arrows to conveniently switch between different warp modes without having
to open the menu. After selecting a mode, you can use the knob to set the depth.

See “Exploring the Warp Modes” on page 49 for detailed information about the available warp
modes.

Pan
Use the PAN knob to control the placement of the waveform in the stereo field (left to right).

Level
Use the LEVEL knob to control the output volume of the oscillator.

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Switching the Last Note Played to a Sample

You can quickly switch the last multisample note
that you played to a single sample. You might do
this if you like a single sound but don’t need the
entire multisample.

Then later, if needed, you can also just as easily

create a wavetable from that sample.

Begin by loading a multisample into an oscillator.

After playing a note, click the Multisample menu
and choose Switch to Single Sample in the menu.

The oscillator switches to Sample mode with the

last-played note loaded as the sample.

To convert the sample to a wavetable, click

the Sample menu and hover over Switch to
Wavetable in the menu.

Multisample Instrument (Note Played)

The menu of import options

appear. These are the same
options that appear when
you import audio as a
wavetable in other areas of
Serum.

Choose one of the menu

options.

The oscillator switches to

Wavetable mode with the
converted wavetable loaded.

See “Importing Multi-Cycle

Waveforms” on page 291
for a detailed description of
each option.

Switch to Wavetable Menu

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Serum features a versatile and intuitive sampler, designed for creatively manipulating and playing
back audio samples. You can load a wide range of audio, from instrument sounds and vocals to field
recordings, offering endless possibilities for sound design and musical experimentation.

In addition to the standard features you would expect in a sampler, Serum includes powerful slicing
tools that are integrated with the CLIP mode within Serum, giving you even greater flexibility to
rearrange and reimagine almost any type of audio source.

You can also quickly and easily convert samples to wavetables, offering even more creative possibilities.

When loading a sample, Serum assumes all samples to be tuned to C3 by default (following
the standard that MIDI Note 69 is A3 at 440 Hz).

You can instruct Serum to assume a different tuning by adding the note name at the end of
the file name. For example, naming a sample file Morning Bass F2.flac tells Serum to
set F2 as the root of your sample, removing the need for you to manually adjust the pitch.

By informing Serum about the root note, Serum can now correctly map the sample. When
you trigger F2, the sample will now play at its original pitch, while playing other notes (such
as G2 or E2) will result in Serum pitch-shifting the sample accordingly.

Similarly, you can include flats and sharps in the file name. This means that naming a sample
file Ashes Piano Eb3.flac or Ashes Piano D#3.flac produces the same result; the
choice is yours whether to use flats or sharps.

Important: The note name (appearing at the end of the file name) must be preceded by a
space or underscore character. No other separators are supported.

Serum additionally refers to pitch data embedded in the instrument chunk of a WAV file.

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Selecting the Sampler

Using OSC A, OSC B, or OSC C, click the header
and choose Sample in the context menu.

The oscillator switches to sample mode.

Sample in the Oscillator Menu

If you already chose a sample in the Granular

or Spectral modes, that sample appears in the
waveform display.

Otherwise, the display is empty.

Sample Instrument

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Click the drop-down menu and choose a sample

from the list of presets.

In addition to tonal and non-tonal factory presets,

you can load Serum wavetables as samples.

You can also load a sample by choosing Load

Sample in the menu and selecting the file using
the dialog that appears.

Note: After loading a sample, you can use

this menu to show the same location on your
computer or reload the sample.

Sample Menu

When a sample loads, the waveform appears in

the display.

Sample Instrument Loaded

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Setting the Sample Start and End

You can easily set the sample start and end points
directly.

Hover over the sample and drag either (or both) of

the markers that appear (on the left or right).

Setting Sample Start and End

Performing Sample Operations

You can perform a range of operations on the
loaded sample.

Right-click the sample and choose an operation

using the context menu.

All operations available in Sample mode

are also available when working in
Granular and Spectral modes.

It’s helpful to become familiar with these

operations in Sample mode before
switching to the other modes.

Sample Operations Menu

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The following describes the operations you can perform:

Operation Description

Show Marker Enable to have the start, end, loop start and loop end markers animate to
Animation show the effect of any assigned modulation. Note that dragging the markers
is not allowed when this option is enabled.
Zoom to Start and Reset the display zoom setting to the default showing both the start and end
End markers.
By default, when this setting is disabled (no check mark present), you can
click-drag up and down in the waveform to zoom in and out, and drag left
and right to pan the waveform left and right.
When enabled (showing a check mark), the waveform maintains a consistent
display showing the entire waveform from start to end, without the ability to
zoom or pan using your mouse.
Important: Selecting this option toggles the setting; you need to deselect
this option to allow you to zoom the display again.
Snap Off The next four menu items relate to how the sample playback start and end
points or loop points are adjusted.

With Snap Off, no snapping is applied. You can place the start and end, or
loop points freely along the waveform, without any restrictions or alignment
to specific reference points.
This provides full flexibility when working with waveforms but requires
careful manual placement to avoid clicks, pops, or timing issues.
Snap to Zero Start, end, or loop points snap to the nearest zero-crossing in the waveform.
A zero-crossing is a point where the waveform amplitude is zero.
This prevents audio clicks or pops when the playback starts, ends, or loops,
as abrupt transitions between non-zero amplitudes can create artifacts. This
is ideal for ensuring smooth playback and transitions in the waveform.
Snap to Beats Start, end, or loop points align to the nearest beat grid, based on the tempo
of your track.
This ensures that the waveform points or loops are musically synchronized
with the track tempo. This is useful for rhythmic or tempo-synced loops,
where precise timing is essential.

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Operation Description

Snap to Loop The start or end points snap to the nearest pre-defined loop points in the
waveform.
This keeps the points aligned with the loop structure, ensuring seamless
looping without unintended offsets. This is helpful when working on a pre-
looped sample or creating a loop that must align perfectly.
Fade Edges Apply a fade-in and fade-out at the start and end of the sample. You can
choose a setting from 1ms to 128ms as well as None.
This helps smooth out any abrupt changes in amplitude that could cause
unwanted artifacts such as clicks or pops when the sample is triggered or
looped.
Normalize Normalize the sample by adjusting its overall volume to maximize the peak
loudness without introducing distortion. This ensures consistent volume
levels while preserving the original dynamics of the sample.
Reverse Reverse the audio sample.
Trim Trim the sample to the current start and end markers.
Slicing Off
Slice Auto See “Slicing Samples” below.
Slice Manual

The Fade Edges, Normalize, Reverse, and Trim operations are non-destructive to the original
sample file.

You can therefore easily undo and redo the operations using the and button
buttons respectively.

In addition, you can choose Reload Sample in the sample menu if you need to clear all
operations and return to the original sample.

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Slicing Samples
Serum can help you slice audio samples into smaller segments, making it easier to trigger specific parts
individually. You can use this technique to create new rhythmic patterns, isolate key elements, or remix a
sample to fit a new sonic context.

Serum offers three slicing options:

• Slicing Off — Turn slicing off

• Slice Auto — Automatically slice the sample using a user-configurable threshold (sensitivity)

• Slice Manual — Automatically slice the sample, and then allow you to manually adjust the slices

The process for slicing samples is identical in Sample, Granular, and Spectral modes.

Auto Slicing

Right-click the sample and choose Slice Auto in

the context menu. Serum automatically slices the
sample.

Notice the yellow horizontal line. This indicates the

slicing threshold (sensitivity). You can move this
line to adjust the slicing threshold.

Dragging the line down decreases the slicing

threshold, producing more slices. Dragging the line
up increases the threshold, resulting in less slices.

Auto Slicing

After setting a threshold, hover the mouse over

the slices. Serum displays the note assigned to the
particular slice.

In this example, the highlighted slice is playable

using A1.

Adjusting the threshold

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Click and drag down and up to zoom in and out of

the slices. You can also zoom in and out using the
mouse wheel.

When you are zoomed in, you can drag left and
right to pan the display.

Zooming In and Out

Manual Slicing

Right-click the sample and choose Slice Manual in

the menu. Serum automatically slices the sample
and then gives you the option to manually adjust
the slices.

Zoom into the slices using your mouse wheel.

Note that zooming using click and drag is disabled
when manual slicing enabled.

Grab a slice handle and move it to the new

location. Continue adjusting other slices, as
needed.
Manually Adjusting Slices
Option-click (macOS) or Alt-click (Windows) to add
a slice. When the cursor is positioned over an
existing slice, Option- or Alt-clicking removes the slice.

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Slicing Options

If you select one of the slicing options (auto or

manual), the following additional options appear in
the context menu.

The following describes the options:

• Play Slice to End — Toggle this option to play

from the triggered slice to the end of the
sample.

Otherwise playback stops at the next slice

marker.

• Play Single Slice — Toggle this option to have

Serum play just one of the slices whenever
any note is triggered.

The playback rate of the slice changes based

on the trigger note (faster rate for notes
higher in the register). You can assign a mod
source to the “single slice” destination to
control which slice is played.

You can use this option in combination with

Play Slice to End to play the entire sample
using any note, with the playback rate
increasing as you move up the register.

• Root Note — Set the note designated to play

the first slice. You can choose any C note
from C-1 to C8.

• Send to Selected Clip (x) — Send the slices to

the currently-selected clip (by default, Clip 1) Extra Slicing Options
in the CLIP module, with each slice assigned
to the corresponding trigger note.

For example, if you select C3 as the root note, choosing this option assigns the slices to successive
notes in the currently-selected clip, starting at C3.

• Auto-Sync to Clip — Similar to the previous option in that the slices are sent to the currently-
selected clip, with each slice assigned to the corresponding trigger note. However, when you
modify the slices (by changing the slice threshold), the clip is automatically modified to reflect the
new slices.

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Loop Menu
Use the loop menu to specify the loop mode for
the sample.

Similar to the sample operations

(described in the previous section),
the loop menu options available in
Sample mode are also available when
working in Granular and Spectral modes.

Sample Loop Menu

You can choose from among the following options:

Option Description

One-shot The sample plays forward for the duration of the note.
This technique is commonly used for sounds like drums, percussion hits, or
sound effects, where the full duration of the sample is essential.
Fwd Loop The sample plays from the start marker to the loop end marker, and then
loops back to the loop start marker. This allows you to play the onset of the
audio and then stay sustained in the loop.
This method is ideal for sustaining sounds, such as a held violin note or a
drone, where you want the sample to maintain a consistent, ongoing tone.
Hover over the sample display and set the loop start and end by dragging
the corresponding blue markers. Click and drag to move the loop to a new
location.

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Option Description

Rev Loop The sample plays from the start marker to the loop end marker and then
reverses playback direction to loop back to loop start, which then loops
backwards to the loop end.
This creates a unique effect where the sound appears to play in reverse
repeatedly, which can add an interesting, unconventional texture to the
music.
Hover over the sample display and set the loop start and end by dragging
the corresponding blue markers. Click and drag to move the loop to a new
location.
Fwd/Rwd Loop The sample plays in a forward/reverse loop for the duration of the note.
Note that the sample plays from the start marker uninterrupted until you
reach the loop.
This creates a seamless, ping-pong-like effect where the sound alternates
between playing forward and in reverse, providing a smooth and
uninterrupted looping experience.
This type of playback is especially useful for creating evolving and dynamic
textures, as it helps avoid the abrupt transitions or potential clicks that can
occur with traditional forward-only looping.
Hover over the sample display and set the loop start and end by dragging
the corresponding blue markers. Click and drag to move the loop to a new
location.
Tailed The sample plays forward from halfway through the sample to the end (the
tail) and then loops the tail of the sample as the amplitude decays.
This allows the sound to fade out naturally rather than cutting off abruptly.
Relative Loop The looped section of the sample changes dynamically based on the
playback start position.
Rather than always looping between fixed start and end points, the loop
moves relative to the playback start marker.
This can be useful when automating or modulating the start position.
Link Loop Length The loop end marker moves relative to the loop start marker, keeping the
loop length consistent.
This can be useful when automating or modulating the loop start position.
Exit Loop on Release When a key is released and the amplitude envelope is in the release phase,
playback exits the loop and plays to the end of the sample.

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Setting the Loop Start and End

You can set the loop start and end points either
by dragging markers or by setting values in the LS
(loop start) and LE (loop end) fields.

To drag markers, hover over the top of the sample

display and drag either of the blue markers that
appear, or between them to drag both together.

Alternatively, click and drag in the LS and LE

fields to move the respective markers. To set a
specific value, double-click the field and type the
appropriate value.
Setting Loop Start and End
You can move the loop start and end markers
while the note is looping to help you find the best
setting.
Use the default modifier (Cmd/Ctrl-click or double-click, depending on GLOBAL setting) between the
markers to reset the loop points to the playback start/end marker positions.

It is not possible to drag the loop markers outside the playback start/end markers.

You can, however, drag, automate, or modulate the markers so that the loop end marker is
before the loop start marker. In this case, the loop direction is reversed.

Setting the Crossfade

You can set a crossfade on a sample loop to
create smoother transitions at the loop points
of the audio sample.

Without a crossfade, loops can sometimes

result in abrupt or noticeable clicks, pops, or
tonal inconsistencies, especially when the
end and start of the loop have mismatched
waveforms.

Crossfading helps address this by blending

the overlapping regions at the loop
boundaries.

Click the button and drag up to set the

crossfade amount. A light blue curve shows
the crossfade graphically.
Setting a Loop Cross Fade

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Setting Sample Parameters

You can set the crossfade, unison (including
detune and blend), and adjust the waveform warp
mode.

You can also adjust the pan and level of the signal.

Sample Parameters

Scan
Use the SCAN knob to set the speed and direction
of the sample playback.

You can adjust the following parameters related to

the scan setting:

• Range — Set the range of the scan knob. The

choices are: +/- 200% (default), +/- 400%,
and +/- 800%.

• Reverse — Reverse the scan direction. You

can automate and modulate this control to
switch playback direction.

• Lock Scan Rate (to Tempo) — Change the

scan rate when the tempo changes.

• Sample Length to BPM — Set the sample

length based on the BPM set in your host
DAW.

The SCAN knob changes to RATE, allowing

you to set the scan rate using beats and bars.

Sample Scan Menu

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Unison
Use the UNISON control to set the number of unison voices, effectively “stacking” oscillators in a way
that is similar to playing multiple notes of the same pitch, but slightly detuned.

Click the field and drag to set the appropriate value. You can also double-click the field and type a value.

This is similar to the unison setting for other oscillator modes.

Note: Unison causes Serum to generate multiple voices, raising CPU usage. The color of the UNISON
field changes as you increase the number of unison voices as a reminder of the CPU consumption.

Click the button to display the unison

settings.

Sample Unison Settings

You can specify the following settings:

Setting Description

MODE Set the detune mode, from among the following:

• Linear — The detuning between each additional voice increases in a

consistent, linear fashion. This means that the pitch of each voice is
spaced evenly in terms of frequency, creating a smooth spread that
retains an even distribution.

This mode can sound very controlled and smooth, giving a thick and
coherent texture.
• Super — Multiple voices are slightly detuned from each other but with a
special emphasis on creating a dense and powerful sound, often with a
slight stereo spread.

Use this mode to create a lush, wide sound, especially with supersaw
sounds, where the detuned voices give a rich, full sonic character.

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Setting Description

MODE (cont.) • Exp — The detuning between voices increases exponentially as

you move away from the central pitch. This means that the spacing
between voices gets wider more quickly as you move outward, creating
a more dramatic spread compared to linear.

This mode can create unique, rich textures, especially for sounds that
need to be more aggressive or have a strong presence in a mix.
• Inv — The detuning behavior is inverted, with lower voices detuned
more sharply compared to higher ones.

Use this mode to create interesting phasing effects or to produce

sounds with a less conventional detuning profile.
• Random — Introduces a random element to the detuning of each voice.
Instead of being evenly spaced, the voices are detuned unpredictably.

This can create a more organic or chaotic sound, ideal for achieving
textures that are less polished and more natural or experimental.
STACK Set the unison stacking.
WIDTH The extent to which the unison voices are spread out across the stereo field,
determining how wide or narrow the resulting sound feels in a stereo mix.

When you increase the width parameter, the unison voices are spread
farther apart in the stereo spectrum, placing some voices more to the left
and others more to the right. This creates a sense of space and a wider,
more immersive sound.

Conversely, decreasing the width narrows the stereo spread, making the
sound more centered and focused. This can be useful for sounds that need
to be more direct or fit better in a dense mix without dominating the stereo
field.
RANGE The extent or range of detuning applied to the unison voices, determining
how far apart in pitch the individual voices are spread around the central
frequency of the original sound.

When the range is set to a low value, the detuning between the unison
voices is minimal. The voices remain relatively close in pitch to the original
frequency, creating a subtle and smooth chorusing effect. This can add
warmth and a slight thickness to the sound without drastically changing its
character.

When the range is increased, the detuning becomes more pronounced,

and the unison voices are spread further apart in pitch. This creates a more
dramatic and sometimes more chaotic or dissonant effect, which can be
useful for creating lush, wide textures or aggressive, detuned leads.

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Setting Description

START Apply a random offset to the starting position for each unison voice.

This creates subtle timing differences, which can make the sound more lively,
complex, and textured.
SPAN Apply a fixed offset to the starting position for each unison voice.
WARP 1 Spread out the warp amount applied to each voice around the current
WARP 1 knob position.
WARP 2 Spread out the warp amount applied to each voice around the current
WARP 2 knob position.

You can further adjust the unison setting using the DETUNE and BLEND knobs.

Unison Detune

Use the DETUNE knob to specify the tuning offset +/- for the additional voices. This is only applicable
when unison is enabled (set to a value above 1).

Unison Blend

Use the BLEND knob to specify the level offset of the unison voices versus the “central” unison voice or
voices (1 if an odd number, 2 if an even number of unison).

You can think of BLEND as a wet/dry mix between a unison (wet) and non-unison (dry) sound. The
default value of 75% is an even blend between all the voices. Note that this is only applicable when the
number of unison voices is greater than two.

Warp
Setting the warp allows you to manipulate the playback/sound of the wavetable oscillator.

By default, warp is set to OFF (as displayed next to the corresponding knob). Clicking the current setting
displays a menu from which you can choose from among the available warp modes.

You can also use the < > arrows to conveniently switch between different warp modes without having
to open the menu. After selecting a mode, you can use the knob to set the depth.

See “Exploring the Warp Modes” on page 49 for detailed information about the available warp
modes.

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Pan
Use the PAN knob to control the placement of the waveform in the stereo field (left to right).

Level
Use the LEVEL knob to control the output volume of the oscillator.

Switching a Sample to a Wavetable

You can quickly and easily create a wavetable from a sample in Serum.

With a sample already

loaded, click the Sample
menu and hover over
Switch to Wavetable in
the menu.

The menu of import

options appears. These
are the same options
that appear when
you import audio as a
wavetable in other areas
of Serum.

Choose one of the

menu options.

The oscillator switches

to Wavetable mode
with the converted
wavetable loaded.

See “Importing Multi- Switch to Wavetable Menu

Cycle Waveforms” on
page 291 for a detailed description of each option.

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Using Granular Synthesis
Serum features an easy-to-use granular synthesis mode that manipulates audio samples by breaking
them down into tiny segments called grains, and then recombining them in various ways to create new
textures and sounds. Each grain typically lasts only a few milliseconds and can be individually controlled
in terms of pitch, shape, duration, and playback speed.

By layering, overlapping, and modifying these grains, you can create complex and evolving soundscapes,
offering a high degree of flexibility and experimentation beyond traditional synthesis methods.

One of the key strengths of granular synthesis is its ability to transform audio in real-time, whether
stretching sounds, altering pitch without affecting duration, or creating rich, atmospheric textures from
even the simplest of recordings. Using the granular mode, you can create everything from shimmering,
ethereal pads to glitchy, fragmented effects, offering limitless possibilities for sonic exploration.

Note: Granular synthesis can be CPU intensive, especially when compared to Wavetable, Sample, or
Multisample modes.

Selecting Granular Synthesis

Using OSC A, OSC B, or OSC C, click the header
and choose Granular in the context menu.

The oscillator switches to granular mode.

Granular in the Oscillator Menu

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If you already chose a sample in the Sample

or Spectral modes, that sample appears in the
waveform display.

Otherwise, the display is empty.

Granular Synthesis

Click the drop-down menu and choose a sample

from the list of presets.

In addition to tonal and non-tonal factory presets,

you can load Serum wavetables as samples.

You can also load a sample by choosing Load

Sample in the menu and selecting the file using
the dialog that appears.

Note: After loading a sample, you can use

this menu to show the same location on your
computer or reload the sample.

Granular Menu

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When a sample loads, the waveform appears in

the display.

Granular Sample Loaded

Setting the Sample Start and End

You can easily set the sample start and end points
directly.

Hover over the sample and drag either (or both) of

the markers that appear (on the left or right).

Setting Sample Start and End

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Performing Granular Operations

You can perform a range of operations on the
loaded sample.

Right-click the sample and choose an operation

using the context menu.

Most of the operations available in Granular mode

are also available in Sample mode. See “Performing
Sample Operations” on page 71 for complete
details about these operations.

Granular Operations Menu

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Loop Menu
Use the loop menu to specify the loop mode for
the sample.

Most of the loop options available in Granular

mode are also available in Sample mode. See
“Loop Menu” on page 77 for more information
about these options.

Setting Loop Grains

You can select Loop Grains using the Loop menu.

This sets the grain playback to respect loop
markers.

Granular Loop Menu

Setting Manual Mode

You can select Manual mode using the loop menu.

When enabled, the playhead is replaced by a red
X|Y dot and the SCAN knob changes to control
the horizontal position of the dot.

When a note is played, the sample does not scan.

Instead, you can freely automate or modulate the
playback position.

You can do this by dragging any mod source to

the X|Y dot to modulate either the position or the
parameter that you assigned to the Y axis (if any).
Manual Mode
Note that slicing is not available when Manual is
selected.

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Setting the Loop Start and End

You can set the loop start and end points either
by dragging markers or by setting values in the LS
(loop start) and LE (loop end) fields.

To drag markers, hover over the top of the sample

display and drag either of the blue markers that
appear, or between them to drag both together.

Alternatively, click and drag in the LS and LE

fields to move the respective markers. To set a
specific value, double-click the field and type the
appropriate value.
Setting Loop Start and End
You can move the loop start and end markers
while the note is looping to help you find the best
setting.
Use the default modifier (Cmd/Ctrl-click or double-click, depending on GLOBAL setting) between the
markers to reset the loop points to the playback start/end marker positions.

It is not possible to drag the loop markers outside the playback start/end markers.

You can, however, drag, automate, or modulate the markers so that the loop end marker is
before the loop start marker. In this case, the loop direction is reversed.

Setting the Crossfade

You can set a crossfade to individual grain
playback.

Click the button and drag up to set the

crossfade amount. A light blue curve shows
the crossfade graphically.

Note that since crossfade is applied to grain

playback, you need to enable Loop Grains in
the loop menu to have this take effect.

Setting a Loop Cross Fade

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Window Amount
Click the button to access the grain amplitude
window settings.

The display changes to show the information you

can set.

Option-click (macOS) or Alt-click

(Windows) and drag the button to
quickly change the window amount
and skew without having to access the
window settings.

Grain Amplitude Window Settings

The following table describes the settings you can specify:

Setting Description

AMOUNT Set the influence of the window curve. You can also set the per-grain
randomization for the amount.
Click the corresponding field and drag to set the appropriate value. You can
also double-click the field and type a value.
SKEW Set the window skew. You can also set the per-grain randomization for the
skew.
Click the corresponding field and drag to set the appropriate value. You can
also double-click the field and type a value.
SHAPE Set the grain window shape. A representation of the corresponding shape
appears on the left.

The shape of each grain determines how its volume evolves over time, affecting the attack and decay
characteristics of the sound. By selecting different grain shapes, such as smooth fades or abrupt cuts,
you can dramatically alter the articulation and texture of the sound.

The following table describes the available grain window shapes:

Shape Description

Hann Apply a smooth, symmetrical fade-in and fade-out to each grain, using a
cosine-shaped envelope to taper the volume.
This creates a soft, natural sound with gradual attacks and decays, reducing
any harsh transitions between grains for a more cohesive texture.

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Shape Description

Welch Shape each grain using a smooth parabolic curve.

This creates a rounded, more focused sound with a strong central emphasis,
producing a natural yet distinct grain structure.
Gaussian Shape each grain using a bell curve, where the volume increases to a peak in
the center and then symmetrically decreases.
This results in a smooth, gentle grain with soft transitions, producing a
natural, rounded sound ideal for creating fluid textures.
Blackman-Harris Apply a windowing function with steep slopes and a smooth central peak,
offering a strong attenuation of the grain’s edges.
This results in grains with a well-defined central focus and minimized
spectral leakage, producing a cleaner, more controlled sound with less
interference between overlapping grains.
Sinc Shape each grain with a distinctive oscillating pattern that gradually fades
out, resembling the sinc function used in signal processing.
This creates a grain with a sharp, precise center and oscillating tails,
producing a unique texture that can add complexity and harmonic richness
to the sound.
Tukey Apply a shape that combines characteristics of both a rectangular and a
tapered window, with a flat center portion and smoothly tapered edges.
This allows for flexible control over the grain’s attack and decay, offering a
balance between sharp transitions and gradual fades, making it useful for
adjusting the grain’s prominence and blending.
Triangle Shape each grain with a linear rise to a central peak followed by a symmetric
linear decay, creating a simple, pointed envelope.
This results in a grain with a clear, sharp attack and a smooth, evenly
tapered release, providing a clean and minimal texture with straightforward
transitions.
Trapezoid Shape each grain with a gradual linear rise, followed by a flat, sustained
middle section, and then a gradual linear decay.
This creates a grain with a more extended, even body, allowing for a
balanced sound that can blend sharp attacks with sustained tones for
smoother transitions and consistent energy.
ExpDec Shape each grain with an exponential decay, where the sound starts at full
volume and quickly fades out in a curved, nonlinear fashion.
This creates a grain with a sharp, pronounced attack followed by a rapid,
smooth decay, useful for producing sharp, percussive textures or gradually
fading sound effects.

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Shape Description

Exp Dec Rev Shape each grain with a reversed exponential decay, where the grain starts
at a low volume and rapidly rises to full volume in a curved, nonlinear
fashion.
This creates a grain with a smooth, swelling attack followed by a sharp peak,
ideal for building tension or creating atmospheric effects with a gradual
onset.

Unison
Use the UNISON control to set the number of unison voices, effectively “stacking” granular oscillators in
a way that is similar to playing multiple notes of the same pitch, but slightly detuned.

Click the field and drag to set the appropriate value. You can also double-click the field and type a value.

This is similar to the unison setting for other oscillator modes.

Note: Unison causes Serum to generate multiple voices, raising CPU usage. The color of the UNISON
field changes as you increase the number of unison voices as a reminder of the CPU consumption.

Click the button to display the unison

settings.

Granular Unison Settings

You can specify the following settings:

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Setting Description

MODE Set the detune mode, from among the following:

• Linear — The detuning between each additional voice increases in a

consistent, linear fashion. This means that the pitch of each voice is
spaced evenly in terms of frequency, creating a smooth spread that
retains an even distribution.

This mode can sound very controlled and smooth, giving a thick and
coherent texture.
• Super — Multiple voices are slightly detuned from each other but with a
special emphasis on creating a dense and powerful sound, often with a
slight stereo spread.

Use this mode to create a lush, wide sound, especially with supersaw
sounds, where the detuned voices give a rich, full sonic character.
• Exp — The detuning between voices increases exponentially as
you move away from the central pitch. This means that the spacing
between voices gets wider more quickly as you move outward, creating
a more dramatic spread compared to linear.

This mode can create unique, rich textures, especially for sounds that
need to be more aggressive or have a strong presence in a mix.
• Inv — The detuning behavior is inverted, with lower voices detuned
more sharply compared to higher ones.

Use this mode to create interesting phasing effects or to produce

sounds with a less conventional detuning profile.
• Random — Introduces a random element to the detuning of each voice.
Instead of being evenly spaced, the voices are detuned unpredictably.

This can create a more organic or chaotic sound, ideal for achieving
textures that are less polished and more natural or experimental.
STACK Set the unison stacking.
DETUNE Specify the tuning offset for the additional voices.
BLEND Specify the level offset of the unison voices versus the “central” unison voice
or voices (1 if an odd number, 2 if an even number of unison).
You can think of BLEND as a wet/dry mix between a unison (wet) and non-
unison (dry) sound. The default value of 75% is an even blend between all
the voices.
Note that this is only applicable when the number of unison voices is greater
than two.

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Setting Description

WIDTH The extent to which the unison voices are spread out across the stereo field,
determining how wide or narrow the resulting sound feels in a stereo mix.
When you increase the width parameter, the unison voices are spread
farther apart in the stereo spectrum, placing some voices more to the left
and others more to the right. This creates a sense of space and a wider,
more immersive sound.
Conversely, decreasing the width narrows the stereo spread, making the
sound more centered and focused. This can be useful for sounds that need
to be more direct or fit better in a dense mix without dominating the stereo
field.
RANGE The extent or range of detuning applied to the unison voices, determining
how far apart in pitch the individual voices are spread around the central
frequency of the original sound.
When the range is set to a low value, the detuning between the unison
voices is minimal. The voices remain relatively close in pitch to the original
frequency, creating a subtle and smooth chorusing effect. This can add
warmth and a slight thickness to the sound without drastically changing its
character.
When the range is increased, the detuning becomes more pronounced,
and the unison voices are spread further apart in pitch. This creates a more
dramatic and sometimes more chaotic or dissonant effect, which can be
useful for creating lush, wide textures or aggressive, detuned leads.
START Apply a random offset to the starting position for each unison voice.

This creates subtle timing differences, which can make the sound more lively,
complex, and textured.
SPAN Apply a fixed offset to the starting position for each unison voice.
SPAWN PATTERN The timing offset at which unison grain voices are spawned.
With Together (default), all unison grain voices spawn at the same time.
With the other options, the spawning of unison grain voices are offset into
the period before the next spawn, as follows:

• Even — The timing of unison grain voices is spread out evenly

• Exp — The timing between unison grain voices increases over the
period before the next spawn
• Random — The timing between unison grain voices is randomly
distributed over the period before the next spawn

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Setting the X|Y Control

If you choose to show the X|Y Control using the
context menu, a red dot appears in the display.

In addition, a new menu option appears in the

context menu allowing you to select the Y axis
parameter.

X|Y Control

Use the context menu to

choose the Y axis parameter.

Y Axis Menu

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The following table describes the available Y axis options:

Option Description

None No Y axis target.

Level The oscillator level.
Warp The WARP 1 setting.
Warp 2 The WARP B setting.
Density The density of the grain cloud.
Grain Length The duration of each grain.
Window Amt The window amount for the sample. Sets the influence of the window curve.
Window Skew The window skew.
Rand Offset The per-grain randomization of the offset.
Rand Dir The per-grain randomization of the direction.
Rand Pitch The per-grain pitch randomization.
Rand Length The per-grain length randomization.
Rand Pan The per-grain randomization of the pan setting.
Rand Gain The per-grain level randomization.
Rand Window The window amount randomization.
Rand Skew The window skew randomization.
Rand Warp The WARP A randomization.
Rand Warp 2 The WARP B randomization.

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After selecting a Y axis

parameter (other than None),
an additional menu option
appears.

This allows you to choose

how to modulate the Y axis
parameter.

Select a modulation option,

as appropriate.

Y Axis Modulation Menu

Setting Granular Parameters

You can set the scan rate, density, and length,
as well as adjust the warp mode, among other
settings.

You can also adjust the pan and level of the signal.

Granular Parameters

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Warp Mode
Setting the warp allows you to manipulate the
playback/sound of the sample.

Click the button to display the warp settings.

Click the button to hide the settings.

By default, warp is set to OFF (as displayed next

to the corresponding knob). Clicking the current Granular Warp Settings
setting displays a menu from which you can
choose from among the available warp modes.

You can also use the < > arrows to conveniently switch between different warp modes without having
to open the menu. After selecting a mode, you can use the knob to set the depth.

See “Exploring the Warp Modes” on page 49 for detailed information about the available warp
modes.

Scan
Use the SCAN knob to set the scan rate. The scan rate controls how quickly the Serum moves through
the audio sample to generate grains.

Granular synthesis involves breaking an audio sample into tiny pieces called grains (usually lasting a few
milliseconds) and then recombining them to create new sounds. Serum determines the playback start
position of a grain by the current playhead position.

The scan rate specifies how quickly the playhead moves through the sample. Setting the scan rate
higher spreads the start positions of grains out along the sample more, resulting in less overlap between
grains.

Setting the scan rate lower causes movement through the sample to slow down. This can produce a
more stretched, evolving, or drone-like sound.

In summary, a higher scan rate can be used to maintain rhythmic accuracy or to create fast-paced,
glitch-like effects. A slower scan rate allows for dramatic time-stretching effects, creating elongated and
ambient textures.

Setting the scan rate to a negative value reverses the direction of the playhead. Alternatively,
setting the scan rate to 0 stops the playhead from moving.

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You can adjust the following parameters

related to the scan setting:

• Range — Set the range of the scan knob.

The choices are: +/- 200% (default), +/-
400%, and +/- 800%.

• Reverse — Reverse the scan direction.

You can automate and modulate this
control to switch playback direction.

• Key Track — Specify how the scan

rate responds to the pitch of the note
played.

With Key Track disabled, the scan rate is

fixed regardless of the key played.

With Key Track enabled, the scan rate

changes in proportion to the pitch of
the note played (higher-pitched notes
increase the scan rate).

• Lock Scan Rate (to Tempo) — Change

the scan rate when the tempo changes.

• Sample Length to BPM — Set the

sample length based on the BPM set in
your host DAW.

The SCAN knob changes to RATE,

allowing you to set the scan rate using
beats and bars.
Granular Scan Menu

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Density
Use the DENS knob to set the density of the grain cloud.

Density defines the rate at which grains are spawned, according to one of three options that you can
specify by right-clicking the knob and choosing from the context menu. The options are:

• Free — Grains are spawned at a rate defined in Hz

• BPM Sync — Grains are spawned at a bar/beat division of host tempo

When selected, the context menu offers Triplet and Dotted as additional options, allowing you to
specify whether triplet or dotted divisions can be selected with the knob.

• Grains — The spawn rate is calculated as a function of grain length such that a consistent number
of grains, as set by the control, is playing at any given time

You can additionally specify two more options using the DENSITY knob context menu.

• Jump Start — Enable this option to have multiple grains spawn at note start so that the full density
is heard immediately.

When disabled, there is only a single spawning at note start and the sound builds to full density
over subsequent spawnings, giving the note a softer start.

• Max Grains — Set to place a limit on the maximum number of grains that can play at any one time,
including unison grain voices.

Many grains playing simultaneously can consume a lot of CPU. Use this option to help reduce this
consumption. If the oscillator tries to spawn a grain when the maximum number is playing, it will
skip and wait until one has stopped playing before it spawns again.

Length
Use the LENGTH knob to set the duration of each grain.

Setting the duration of each grain allows you to control how long each sound fragment lasts, influencing
the overall character of the resulting texture. Shorter grains can produce sharper, more rhythmic sounds,
while longer grains create smoother, more sustained tones.

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You can specify how the length is determined by right-clicking the LENGTH knob and choosing one of
three options from the context menu:

• Free — Gain length can be set in seconds or milliseconds

• BPM Sync — Grain length can be set to a bar/beat division of host tempo

When selected, the context menu offers Triplet and Dotted as additional options, allowing you to
specify whether triplet or dotted divisions can be selected with the knob.

• Percent — Grain length is set to a percent of the density period. Note that this option is not
available if you select the Grains option with the DENSITY knob.

Pan
Use the PAN knob to control the placement of the sample in the stereo field (left to right).

Level
Use the LEVEL knob to control the output volume of the oscillator.

Setting the Grain Randomization

You can set the grain randomization parameters by
adjusting the lower row of knobs.

Grain Randomization

The following table describes the available knobs:

Knob Description

OFFSET Set the per-grain randomization of the offset.

DIR Set the per-grain randomization of the direction.
PITCH Set the per-grain pitch randomization.
RAND (LENGTH) Set the per-grain length randomization.
RAND (PAN) Set the per-grain randomization of the pan setting.
RAND (LEVEL) Set the per-grain level randomization.

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Reversing the Grain Playback Direction Randomization

You can reverse grains as part of the per-grain
direction randomization.

Right-click the DIR knob and choose Reverse

Grains in the context menu to toggle the reverse
grains feature on or off.

You can automate and modulate this setting to

switch playback direction of all grains at once.

Grain Randomization

Switching a Sample to a Wavetable

You can quickly and easily create a wavetable from a sample in Serum.

With a sample already

loaded, click the
Granular menu and
hover over Switch to
Wavetable in the menu.

The menu of import

options appears. These
are the same options
that appear when
you import audio as a
wavetable in other areas
of Serum.

Choose one of the

menu options.

The oscillator switches

to Wavetable mode
with the converted
wavetable loaded.

See “Importing Multi- Switch to Wavetable Menu

Cycle Waveforms” on
page 291 for a detailed description of each option.

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Serum features a spectral synthesis mode that generates sound by analyzing and manipulating the
frequency spectrum of a sound, breaking it down into its individual frequency components or partials.
Unlike other synthesis methods that operate directly on the waveform, spectral synthesis focuses on the
harmonic and inharmonic content, allowing for precise control over the timbre and evolution of sound.

By altering specific frequency bands, adding or removing harmonics, or even shifting spectral content
over time, this approach can create complex, evolving textures that can range from natural acoustic-like
tones to entirely synthetic soundscapes. In practical use, spectral synthesis opens up unique possibilities
for morphing and transforming sound in ways that are not achievable with other synthesis techniques.

For instance, by isolating and processing specific frequencies, it is possible to create sounds that
gradually shift from one texture to another, or blend multiple sources into a single, coherent output.
Additionally, spectral synthesis allows for dynamic filtering and precise spectral editing.

Note: This method can be CPU intensive but provides unparalleled flexibility in shaping sound at a
fundamental, spectral level.

Selecting Spectral Synthesis

Using OSC A, OSC B, or OSC C, click the header
and choose Spectral in the context menu.

The oscillator switches to spectral mode.

Spectral in the Oscillator Menu

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If you already chose a sample in the Sample or

Granular modes, that sample appears in the
spectral display.

Otherwise, the display is empty.

Spectral Synthesis

Click the drop-down menu and choose a sample,

as needed.

In addition to tonal and non-tonal factory presets,

you can load Serum wavetables as samples.

You can also load a sample by choosing Load

Sample in the menu and selecting the file using
the dialog that appears.

Note: After loading a sample, you can use

this menu to show the same location on your
computer or reload the sample.

Spectral Menu

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When a sample loads, the spectral representation

appears in the display.

Click and drag up and down in the frequency

spectrum to zoom the display.

You can tell if the display is fully zoomed out by

hovering over the display and checking whether
you can see both the start and end markers.

Spectral Waveform

Setting the Sample Start and End

You can easily set the sample start and end points
directly.

Hover over the sample and drag either (or both) of

the markers that appear (on the left or right).

Setting Sample Start and End

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Setting the Sample High and Low Frequencies

You can set the sample high and low frequency
points directly by dragging the markers to the right
of the spectrogram, as needed.

Right-click in the high-low pane to display the

context menu. You can toggle options on and off
using this menu.

Setting Sample Hi and Low

The following table describes the options you can choose:

Option Description

Smooth Apply a fourth-order Butterworth filter at the low and high frequency
boundaries, for smoother edges.
Post Warp Apply the low/high filtering after processing spectral warps.

You can drag and drop any modulation

source (envelopes and LFOs) to the high
and low frequency markers to modulate
the respective control.

Modulating the Low Frequency

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Performing Sample Operations

You can perform a range of operations on the
loaded sample.

Right-click the sample and choose an operation

using the context menu.

Most of the operations available in Spectral mode

are also available in Sample mode. See “Performing
Sample Operations” on page 71 for complete
details about these operations.

Spectral Context Menu

Showing the Waveform Display

To toggle the display of the waveform directly

below the spectral display, right-click the sample
and choose Show Waveform Display in the
context menu.
Deselect the option to hide the waveform display.

Waveform Display

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Loop Menu
Use the loop menu to specify the loop mode for
the sample.

Most of the loop options available in Spectral

mode are also available in Sample mode. See
“Loop Menu” on page 77 for more information
about these options.

Spectral Loop Menu

Setting Manual Mode

You can select Manual mode using the loop menu.

When enabled, the playhead is replaced by a red
X|Y dot and the SCAN knob changes to control
the horizontal position of the dot.

When a note is played, the sample does not scan.

Instead, you can freely automate or modulate the
playback position.

You can do this by dragging any mod source to

the X|Y dot to modulate either the position or the
parameter that you assigned to the Y axis (if any).
Manual Mode
Note that slicing is not available when Manual is
selected.

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Setting the Loop Start and End

You can set the loop start and end points either
by dragging markers or by setting values in the LS
(loop start) and LE (loop end) fields.

To drag markers, hover over the top of the sample

display and drag either of the blue markers that
appear, or between them to drag both together.

Alternatively, click and drag in the LS and LE

fields to move the respective markers. To set a
specific value, double-click the field and type the
appropriate value.
Setting Loop Start and End
You can move the loop start and end markers
while the note is looping to help you find the best
setting.
Use the default modifier (Cmd/Ctrl-click or double-click, depending on GLOBAL setting) between the
markers to reset the loop points to the playback start/end marker positions.

It is not possible to drag the loop markers outside the playback start/end markers.

You can, however, drag, automate, or modulate the markers so that the loop end marker is
before the loop start marker. In this case, the loop direction is reversed.

Setting the Crossfade

You can set a crossfade on a sample loop to
create smoother transitions at the loop points
of the audio sample.

Click the button and drag up to set the

crossfade amount. A light blue curve shows
the crossfade graphically.

Setting a Loop Cross Fade

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Unison
Use the UNISON control to set the number of unison voices, effectively “stacking” oscillators in a way
that is similar to playing multiple notes of the same pitch, but slightly detuned.

Click the field and drag to set the appropriate value. You can also double-click the field and type a value.

This is similar to the unison setting for other oscillator modes.

Note: Unison causes Serum to generate multiple voices, raising CPU usage. The color of the UNISON
field changes as you increase the number of unison voices as a reminder of the CPU consumption.

Click the button to display the unison

settings.

Spectral Unison Settings

You can specify the following settings:

Setting Description

MODE The detune mode, from among the following:

• Linear — The detuning between each additional voice increases in a

consistent, linear fashion. This means that the pitch of each voice is
spaced evenly in terms of frequency, creating a smooth spread that
retains an even distribution.

This mode can sound very controlled and smooth, giving a thick and
coherent texture.
• Super — Multiple voices are slightly detuned from each other but with a
special emphasis on creating a dense and powerful sound, often with a
slight stereo spread.

Use this mode to create a lush, wide sound, especially with supersaw
sounds, where the detuned voices give a rich, full sonic character.

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Setting Description

MODE (cont.) • Exp — The detuning between voices increases exponentially as

you move away from the central pitch. This means that the spacing
between voices gets wider more quickly as you move outward, creating
a more dramatic spread compared to linear.

This mode can create unique, rich textures, especially for sounds that
need to be more aggressive or have a strong presence in a mix.
• Inv — The detuning behavior is inverted, with lower voices detuned
more sharply compared to higher ones.

Use this mode to create interesting phasing effects or to produce

sounds with a less conventional detuning profile.
• Random — Introduces a random element to the detuning of each voice.
Instead of being evenly spaced, the voices are detuned unpredictably.

This can create a more organic or chaotic sound, ideal for achieving
textures that are less polished and more natural or experimental.
STACK The unison stacking.
DETUNE The tuning offset for the additional voices.
BLEND The level offset of the unison voices versus the “central” unison voice or
voices (1 if an odd number, 2 if an even number of unison).
You can think of BLEND as a wet/dry mix between a unison (wet) and non-
unison (dry) sound. The default value of 75% is an even blend between all
the voices.
Note that this is only applicable when the number of unison voices is greater
than two.
WIDTH The extent to which the unison voices are spread out across the stereo field,
determining how wide or narrow the resulting sound feels in a stereo mix.

When you increase the width parameter, the unison voices are spread
farther apart in the stereo spectrum, placing some voices more to the left
and others more to the right. This creates a sense of space and a wider,
more immersive sound.

Conversely, decreasing the width narrows the stereo spread, making the
sound more centered and focused. This can be useful for sounds that need
to be more direct or fit better in a dense mix without dominating the stereo
field.

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Setting Description

RANGE The extent or range of detuning applied to the unison voices, determining
how far apart in pitch the individual voices are spread around the central
frequency of the original sound.

When the range is set to a low value, the detuning between the unison
voices is minimal. The voices remain relatively close in pitch to the original
frequency, creating a subtle and smooth chorusing effect. This can add
warmth and a slight thickness to the sound without drastically changing its
character.

When the range is increased, the detuning becomes more pronounced,

and the unison voices are spread further apart in pitch. This creates a more
dramatic and sometimes more chaotic or dissonant effect, which can be
useful for creating lush, wide textures or aggressive, detuned leads.
SPAN Apply a fixed offset to the starting position for each unison voice.
START Apply a random offset to the starting position for each unison voice.

This creates subtle timing differences, which can make the sound more lively,
complex, and textured.
WARP 1 Spread out the warp amount applied to each voice around the current
WARP 1 knob position.
WARP 2 Spread out the warp amount applied to each voice around the current
WARP 2 knob position.

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Setting the X|Y Control

If you choose to show the X|Y Control using the
context menu, a red dot appears in the spectral
display.

In addition, a new menu option appears in the

context menu allowing you to select the Y axis
parameter.

X|Y Control

Use the context menu to

choose the Y axis parameter.

Y Axis Menu

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The following table describes the available Y axis options:

Option Description

None No Y axis target.

Level The oscillator level.
Warp The WARP 1 setting.
Warp 2 The WARP 2 setting.
Spec Flt Cutoff The spectral filter cutoff.
Spec Flt Wet/Dry The spectral filter mix (wet/dry).
Freq Lo The low frequency (near the bottom right of the spectral display).
Freq Hi The high frequency (near the top right of the spectral display).

After selecting a Y axis parameter

(other than None), an additional
menu option appears.

This allows you to choose

how to modulate the Y axis
parameter.

Select a modulation option, as

appropriate.

Y Axis Modulation Menu

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 Using Spectral Synthesis

Setting Spectral Parameters

You can set the sample playback, spectral filter
cutoff, and adjust the waveform warp mode.

You can also adjust the pan and level of the signal.

Spectral Parameters

Scan
Use the SCAN knob to set the speed and direction
of the sample playback.

You can adjust the following parameters related to

the scan setting:

• Range — Set the range of the scan knob. The

choices are: +/- 200% (default), +/- 400%,
and +/- 800%.

• Reverse — Reverse the scan direction. You

can automate and modulate this control to
switch playback direction.

• Key Track — Specify how the scan rate

responds to the pitch of the note played.

With Key Track disabled, the scan rate is fixed

regardless of the key played.

With Key Track enabled, the scan rate

changes in proportion to the pitch of the note
played (higher-pitched notes increase the
scan rate).

• Lock Scan Rate (to Tempo) — Change the

scan rate when the tempo changes.

• Sample Length to BPM — Set the sample

length based on the BPM set in your host
DAW.

The SCAN knob changes to RATE, allowing

you to set the scan rate using beats and bars.

Spectral Scan Menu

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Setting the sample length to BPM allows drum loops or samples to sync with the DAW tempo while still
letting you pitch the sample up and down using the keyboard while keeping the tempo consistent.

You can also control the phase lock and transients.

• Phase Lock — Adjust the FFT phases to minimize the audible phase change between FFT blocks

This can result in a less “smeared” sound, more faithful to the original sample. Consider using this
with tonal samples.

• Transients — Preserves transients that would otherwise be smeared by FFT processing

Consider using this with percussive sounds or drum loops.

Cut
Use the CUT knob to set the cutoff of the spectral filter.

This sets the cutoff point of the spectral filter, determining which frequencies are allowed to pass
through or are filtered out.

By adjusting the CUT knob, you can control the range of frequencies that shape the sound, effectively
removing unwanted high or low spectral content to refine the tone and texture of the output.

Filter
You can create a custom filter curve, choose a filter preset, or choose a wavetable to act as the filter.

Creating a Custom Curve

Click the FILTER display to show the spectral filter

editor.

Filter Display

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 Using Spectral Synthesis

The spectral filter editor appears in

a dialog.

Spectral Filter Mask Editor

Modify the filter by adding new

points and dragging curves.

Spectral Filter Mask Editor (Modified)

The following table describes operations you can perform when editing the filter:

Operation Graph Description

Double-click Add a new point to the mask or remove an

existing point.

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Operation Graph Description

Drag a point Move a point to a new location.

Drag a curve point Create or modify a curve between points.

Option/Alt drag a point Move a point to a new location, constrained

to the current grid.

Option/Alt drag a curve Create or modify curves between all points

point simultaneously.

Click and drag to select Select multiple points. This allows you to drag
multiple points simultaneously.

Click and drag in the GRID field to set the number of grid divisions. To set a specific value, double-click
the field and type the appropriate value.

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Choosing a Filter Preset

You can choose a factory filter

preset, click the FILTER display to
show the spectral filter editor.

In the filter editor, click the

button and choose a preset
in the context menu.

After the preset loads, you can

modify the filter curve as needed.
Use the menu to save the preset
for future use.

Alternatively, choose Default in

the menu to return to the draft
filter curve.
Filter Presets Menu

Choosing a Wavetable

To use a wavetable as a filter, right-click the

FILTER display and choose a curve in the context
menu.

After choosing a preset, a thumbnail of the filter

shows to indicate your selection.

Important: It’s not possible to edit the filter if you

selected a wavetable.

Filter Menu

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To return to creating a custom filter, right-click

the FILTER display and choose Curve Filter in the
menu.

You can then click the FILTER display, as before, to

display the spectral filter editor.

Mix Filter Selected

Use the MIX knob to control the balance between the wet (processed) and dry (unprocessed) signal.

Setting the Warp Mode

Setting the warp allows you to manipulate the playback/sound of the sample.

By default, warp is set to OFF (as displayed next to the corresponding knob). Clicking the current setting
displays a menu from which you can choose from among the available warp modes.

You can also use the < > arrows to conveniently switch between different warp modes without having
to open the menu. After selecting a mode, you can use the knob to set the depth.

See “Exploring the Warp Modes” on page 49 for detailed information about the available warp
modes.

Pan
Use the PAN knob to control the placement of the sample in the stereo field (left to right).

Level
Use the LEVEL knob to control the output volume of the oscillator.

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Switching a Sample to a Wavetable

You can quickly and easily create a wavetable from a sample in Serum.

With a sample already

loaded, click the
Spectral menu and
hover over Switch to
Wavetable in the menu.

The menu of import

options appears. These
are the same options
that appear when
you import audio as a
wavetable in other areas
of Serum.

Choose one of the

menu options.

The oscillator switches

to Wavetable mode
with the converted
wavetable loaded.

See “Importing Multi-

Cycle Waveforms” on Switch to Wavetable Menu
page 291 for a detailed
description of each option.

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Using the Sub Oscillator
Serum features a sub oscillator that generates a waveform pitched below the primary oscillators,
adding depth and weight to the low end of a sound. You can select from a variety of simple waveforms,
including sine, square, triangle, and more, providing a clean, stable foundation without introducing
excessive harmonic complexity.

Using the sub oscillator enhances bass presence by reinforcing low frequencies, giving your sound more
power and fullness. This is especially useful for creating bass-heavy sounds like sub-bass, deep bass for
electronic music, or warm, rich pads.

The sub oscillator also helps create a thicker, more robust tone, making it ideal for leads, plucks, and
pads, as it adds body without overwhelming the higher frequencies.

Sub Oscillator

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Exploring the Sub Oscillator

To enable the sub oscillator, click the header (with the oscillator name and power button). When
enabled, the button turns green.

Enabling the SUB Osc SUB Osc Enabled

You can set several parameters related to the sub oscillator.

Pitch
Use the OCT (octave) and CRS (coarse) controls to alter the pitch of the waveform.

The CRS setting controls the pitch transpose that tunes or detunes continuous (no snap) semitones.
CRS is most useful as a modulation destination or automation parameter.

Waveform
You can select the waveform to use as the basis of the sub oscillator. The following table describes the
waveform options:

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Icon Waveform Description

Sine A sine wave is a smooth, pure waveform that contains only the
fundamental frequency, without any harmonics or overtones.
It produces the cleanest and most basic form of sound,
characterized by its rounded, steady oscillation.
A sine wave is particularly effective at reinforcing the lowest
frequencies without adding any additional complexity to the
sound.
This makes it ideal for creating deep, focused sub-bass, as it
delivers a pure and powerful low end that sits well in a mix
without clashing with other frequencies.
Rounded Rect A rounded rectangle wave is a variation of the square wave that
has smoother transitions between its high and low points, as
opposed to the sharp, immediate jumps of a traditional square
wave.
This results in a waveform that still has a pronounced pulse-like
quality but with a less harsh, more rounded sound due to the
gentler edges.
A rounded rect wave produces a sound with some harmonic
content but softer than that of a square wave, making it useful
for adding more depth and texture to the low end without being
too aggressive.
It strikes a balance between the pure, smooth tone of a sine wave
and the rich harmonic content of a square wave.
Triangle A triangle wave is a simple waveform that resembles a triangle in
shape, with a linear rise and fall.
It is similar to a sine wave in that it emphasizes the fundamental
frequency, but it has a small amount of harmonic content,
primarily odd harmonics, giving it a slightly richer sound than a
sine wave, though still softer and smoother than a square wave.
A triangle wave adds depth to the low end with a bit more
texture and brightness than a sine wave, while still maintaining a
relatively clean sound.
It’s a great choice for adding subtle harmonic detail to a bassline
without overpowering other elements in the mix, making it
effective in genres that require both warmth and clarity in the
lower frequencies.

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Icon Waveform Description

Saw A sawtooth wave is a waveform characterized by a sharp rise
followed by an abrupt drop, containing both odd and even
harmonics. This rich harmonic content makes it one of the most
complex and versatile waveforms in synthesis.
When used in a sub oscillator, a saw wave can add a much more
aggressive and gritty texture to the low end. It introduces not
only the fundamental bass frequency but also a wide range of
harmonics that give the sound a bright and energetic character.
This makes the saw wave useful for creating powerful, bold
basslines that cut through a mix, especially in genres like dubstep,
techno, and electro, where a more pronounced and dynamic low
end is desired.
However, because the saw wave is so harmonically rich, it can
sometimes overpower the other elements in the mix if not
carefully managed.
In the sub oscillator role, it can be used to fatten up a sound,
adding both depth and brightness, but it should be applied
when you want your low-end frequencies to have a strong
presence and a more complex tonal quality compared to simpler
waveforms like sine or triangle waves.
Square A square wave is a waveform that alternates sharply between its
high and low states, creating a distinct, pulse-like sound. It is rich
in odd harmonics, which gives it a fuller, more aggressive tone
compared to smoother waveforms like sine or triangle waves.
A square wave can add a bold, punchy quality to the low end. Its
strong harmonic presence makes it ideal for basslines that need
to stand out or cut through a dense mix, especially in genres like
electronic, rock, and synthwave.
The square wave’s harmonics provide additional texture and
brightness, making the bass sound more present and dynamic
compared to simpler waveforms.
However, the sharp transitions of a square wave can sometimes
produce a harsher sound in the low frequencies. This makes it a
good choice when you want your bass to have an assertive, more
aggressive edge, adding character and energy to the foundational
elements of a track.
Pulse A pulse wave is a variation of the square wave where the high
and low states are not equal, resulting in an asymmetrical
waveform.

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Phase
Use the PHASE control to specify where the oscillator should begin playing back when a note is
triggered. This is similar to the phase control in other parts of Serum. It is also the same concept as
sample start on a sampler (except the sub oscillator “sample” is a very small waveform).

Right-click the PHASE control and choose Contiguous in the menu that appears to have new notes
continue with the phase of the previous note.

Pan
Use the PAN knob to control the placement of the waveform in the stereo field (left to right).

Level
Use the LEVEL knob to control the output volume of the sub oscillator.

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Using the Noise Oscillator
Serum features a dedicated noise oscillator that offers a wide range of factory-supplied noise samples
that you can use to add depth, texture, realism, and expressiveness to your sound design.

Since the noise oscillator is actually a stereo sample player featuring high-quality playback, you can also
use it to load your own samples for even greater versatility.

For example, you could use the noise oscillator as a modulation source for many parameters (though the
results can, admittedly, be chaotic). Samples like drum loops, for example, can lead to very interesting
results.

The noise oscillator also appears in the WARP section of all three wavetable oscillators, allowing you to
apply frequency, phase, amplitude, and ring modulation (using the sampler as the modulator).

Noise Oscillator

When using the noise oscillator as a modulator, you should turn down the volume of the
noise oscillator (to just take advantage of the modulation effect).

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Exploring the Noise Oscillator

To enable the noise oscillator, click the header (with the oscillator name and power button). When
enabled, the button turns green.

Enabling the Noise Osc Noise Osc Enabled

Loading a Preset
To load a noise preset, click the current sample name and
choose an option in the menu that appears.

After choosing a preset, you can use the < > arrows to
conveniently switch between noise samples without having
to open the menu.

Note that there is a separate category for noises named after

colors.

If you choose one of the noise color modes, a

STEREO control becomes available.

At a setting of 0, the noise is mono; at 100, there is

no correlation between left and right signals.

In addition, a FILTER knob is available to high or

low pass the signal offering you further control.

Noise Menu

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The following table offers a brief description of the difference between these different noises:

Noise Color Description

White White noise has equal energy at all frequencies, meaning it covers the entire
audible spectrum (20 Hz to 20 kHz) with equal intensity.
It sounds like a constant hiss or the static between radio stations.
Because of its equal distribution across frequencies, white noise has a bright,
harsh sound.
Pink Pink noise has equal energy per octave, which means the energy decreases
as the frequency increases. Specifically, it has 3 dB less energy per octave as
the frequency doubles.
It has a warmer, less harsh sound compared to white noise, with more
emphasis on lower frequencies.
Brown Brown noise, also called Brownian noise or red noise, has energy that
decreases even more rapidly than pink noise, at 6 dB per octave.
It has a deep, rumbling sound, with much more emphasis on lower
frequencies and very little high-frequency content.
Geiger Geiger noise doesn’t have a uniform frequency spectrum like the others.
Instead, it is chaotic, consisting of random clicks or bursts that are not evenly
distributed across time or frequency.
It sounds like the clicks of a Geiger counter, hence the name. The noise is
made up of sporadic, random bursts with unpredictable intervals between
them.

Loading a Sample
Noise oscillator sounds are simply mono or stereo WAV files. This means that you can use your own
samples as noise sounds.

To load your own sample in the noise oscillator, click the current sample name to display the NOISE
menu and choose Load Sample. A dialog appears allowing you to locate the sample on your computer.

Alternatively, drag a sample from the Finder (macOS) or Explorer (Windows) to the oscillator waveform
pane.

Embedding the Sample in the Preset

You can embed a noise sample into your preset (when saving the preset) by displaying the NOISE menu
and choosing Embed in Preset.

This allows you to streamline your presets by packaging your noise samples together with the Serum
settings.

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Noise oscillator playback uses high-quality real time interpolation. This is because with
noise sounds, the high-frequencies are important. Serum strives to offer the best quality
whenever possible, even at the expense of additional CPU usage (although this feature is
heavily optimized with both SSE2 and pre-calculations when a file loads).

Since high-quality playback does require more CPU processing, it is worth noting that
mono sounds do use slightly less CPU resources (one channel instead of two can add up
with chords). The main consideration here is that if you have a mono noise source, don’t
export it as a stereo file for Serum since you will be wasting both disk space and CPU
resources (on playback).

One Shot/Looping
By default, the noise oscillator is set to loop samples.

This is indicated by the highlighted looping button.

Select the (one shot) switch to have the sample (noise) stop when playback reaches the end
of the sound file.

The button highlights to show that it’s enabled.

Looping is typically good with noise sounds, but one-shot mode is useful for attack sounds (to add a
percussive punch/attack transient to a sound, for instance).

Start
Use the START control to set the phase start (as a percentage). Click and drag in the field to set the
value. Alternatively, double-click the field and type the appropriate value.

This setting for the noise oscillator is similar to the phase controls in other parts of Serum. However,
since a noise sound is a lot longer than an oscillator waveform, it might be easier to think of this as
“sample start.”

You can also automate the control, which results in a sort of lo-fi “scratching” effect.

Random
Use the RAND control to randomize the start phase. This prevents the noise from being identical each
time you press a note.

Holding a chord is a good example of when you would likely want to add randomness, otherwise the
same noise sounds for all the notes.

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Pitch
Use the PITCH knob to specify the base pitch/frequency for the noise oscillator. The default (50%) is
nominal pitch, that is, the original pitch of the sound file (assuming that the keytrack switch is off).

Fine
Use the FINE knob to fine tune the pitch setting.

Pan
Use the PAN knob to control the placement of the noise in the stereo field (left to right).

Level
Use the LEVEL knob to control the output volume of the noise oscillator.

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Using the Filter Modules
Serum features an advanced filter module that offers per-voice filtering of one or more oscillators.
Filters are one of the most powerful tools for shaping and sculpting sound, allowing you to modify the
frequency content of a sound, selectively emphasizing or reducing certain frequencies.

By controlling which parts of the sound’s spectrum are allowed to pass through and which are cut off,
you can use Serum’s filters to drastically alter a sound’s character, making it warmer, brighter, darker, or
even more aggressive.

Serum includes an extensive collection of filters, featuring numerous variations on low-pass, high-pass,
band-pass, notch, comb, and more. Combined with Serum’s extensive modulation capabilities, you can
use the filters to create a range of sounds including rhythmic sweeps, evolving pads, and even vocal-like
formant sounds.

With playful tweaking and clever modulation, you can use the filter module as a creative playground,
exploring endless possibilities for sound manipulation and transformation.

Serum Filter Modules

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Exploring the Filter Modules

To enable or disable a filter module, click the corresponding power button. This offers you an easy way
to disable a filter entirely, if needed.

Enabling Filter 1 and 2 Filter 1 and 2 Enabled

Routing an Oscillator
To route an oscillator to a specific filter module, select the
corresponding switch:

• S - SUB oscillator

• A - OSC A

• B - OSC B

• C - OSC C

• N - NOISE oscillator

Filter Routing

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Filter Type
To choose a filter type, click the current filter setting. A
pop-up menu appears showing a hierarchical collection of
available filter types.

Use the < > arrows to conveniently switch between filter

types without having to open the menu.

Alternatively, hover over the menu and use the mouse wheel
to quickly rotate through menu options.

Filter Menu

Filter Types and Var Parameter Functions

The following table describes the available filter types:

Category Filter Type Description Var Function

Normal MG Low Ladder Low-Pass Filter. FAT: Add saturation to the

6/12/18/24 The number represents filter resonance signal path.
the db per octave slope of
the filter. This has a taming effect on
filter resonance and enriches
The topology is based on the resulting harmonic
filters made famous in content.
classic Moog synthesizer
designs.
Low 6/12/18/24 State-Variable Low-Pass FAT: Add saturation to the
Filter. filter resonance signal path.
This has a taming effect on
The number represents
filter resonance and enriches
the db per octave slope of
the resulting harmonic
the filter.
content.

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Category Filter Type Description Var Function

Normal (cont.) High 6/12/18/24 State-Variable High-Pass FAT: Add saturation to the
Filter. filter resonance signal path.
The number represents This has a taming effect on
the db per octave slope of filter resonance and enriches
the filter. the resulting harmonic
content.
Band/Peak/Notch State-Variable Band/Peak/ FAT: Add saturation to the
12/24 Notch Filter. filter resonance signal path.
This has a taming effect on
filter resonance and enriches
the resulting harmonic
content.
Multi LH/LB/LP/LN/ Dual SVF Filters. FREQ: Set the cutoff
HB/HP/HN/BP/ frequency of the second SVF
BN/PP/PN/NN The first letter is primary,
filter.
the second letter is
secondary (for example,
BP is Band+Peak).
The resonance control
applies equally to both
filters.
LBH/LPH/LNH/ Morphing SVF filters (for MORPH: Smoothly transition
BPN example, Lowpass <-> between the filter states.
Bandpass <-> Highpass)
Flanges Cmb L/Flg L/Phs L Comb/Flanger/Phaser LP FREQ: Set the cutoff
with a low-pass filter in frequency of the low pass
the internal feedback filter affecting the internal
circuit. feedback circuit.
Set the MIX knob to 50%
for best results.
Cmb H/Flg H/Phs Comb/Flanger/Phaser HP FREQ: Set the cutoff
H with a high-pass filter frequency of the high-pass
in the internal feedback filter affecting the internal
circuit. feedback circuit.
Set the MIX knob to 50%
for best results.
Cmb HL/Flg HL/ Comb/Flanger/Phaser HL WID: Expand the
Phs HL with a high pass + low bandwidth allowed through
pass filter in the internal the internal feedback circuit
feedback circuit. around the filter cutoff
frequency.
Set the MIX knob to 50%
for best results.

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Category Filter Type Description Var Function

Misc Low/Band/High Filters with morphable DB +/-: Increase or decrease

EQ 6/12 frequency responses. gain of the pass band.
The number represents Extreme settings morph the
the db per octave slope frequency response of the
of the filter. Resonance filter, for example, the Low
has no effect on 6 db per EQ 12 filter blends from a
octave variations. high pass (when db gain is set
to 0) to a low shelf.
Ring Mod/Ring Apply ring modulation SPREAD (only available in the
Modx2 to the input signal at x2 filter variant):
a frequency set by the
cutoff control. Control the distance between
the first and second ring
The x2 variant features a modulator frequencies.
second ring modulation.
SampHold/ Apply a sample-and-hold N/A
SampHold- distortion.
The minus variant
outputs the difference
of the sample-and-hold
distortion and the input
signal.
Combs/Allpasses/ Generate phase smearing DAMP: Soften the feedback
Reverb through combinations of path of the filter.
delays and all-pass filters.
French LP Unique distorting low- BOEUF: A secondary
pass filter. resonance control.
Combinations of the primary
The filter responds non-
and Boeuf resonance values
linearly to input signals.
produce unique results.
German LP “Zero-Delay Feedback” N/A
low-pass filter.
Add Bass Phase-rotated low pass THRU: Add a phase-rotated
filter with a touch of drive. dry signal.
Not a typical synth filter,
but maybe you’ll find a
use!

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Category Filter Type Description Var Function

Misc (cont.) Formant-I/II/III Formant ‘vowel’ filters. FORMNT: Shift the formants
to generate a broader
The CUTOFF knob
range of possible filter
morphs between various
permutations.
formants. This is great
for adding vocal-like
characteristics to patches.
Bandreject Attenuate a specific range WIDTH: Adjust the
to very low levels. It has overall width of the filter’s
the opposite effect of a attenuated “notch”.
band-pass filter.
Dist.Comb 1/2 LP/ Combination comb filter COMBFRQ: Set the
BP and pass filter. frequency of the comb filter.

The comb filter (version

1 is a positive feedback
comb filter; version 2 is a
negative feedback comb
filter) is applied to the
feedback path of the pass
filter.
Scream LP/BP A high-feedback filter SCREAM: Set the cutoff
effect that can have a frequency for the feedback
scream-like quality. circuit.

The DRIVE knob affects

the amount of scream (raise
DRIVE above 50% to hear
the scream).
New Wsp Circuit model of a classic MORPH: Blend between
synth filter that buzzes LPF/Notch/HPF.
(and burbles!).
DJ Mixer Xfer freeware DJM filter N/A
plugin.

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 Using the Filter Modules

Category Filter Type Description Var Function

New (cont.) Diffusor All-pass diffusor stage STAGES: Specify how many
for making things sound APF stages are used.
phasey and blurry in a
cool way.
MG Ladder Clean circuit model of SMOOTH: Slow the rate
classic transistor ladder at which the cutoff is
VCF. modulated.
Acid Ladder Circuit model of a diode SMOOTH: Slow the rate
ladder VCF ubiquitous in at which the cutoff is
acid music. modulated.
EMS Ladder Clean circuit model of the SMOOTH: Slow the rate
VCF that makes Dr. Who at which the cutoff is
sounds. modulated.
MG Dirty MG Ladder, but all the PAIN: How far you’re holding
distortion is there and you a lighter from the circuit
are overdriving the circuit. board (this is physically
correct; not a joke).
PZ SVF Drawable filters. SMOOTH: Slow the rate
at which the cutoff is
modulated.
Comb 2 Comb filter with crazy FRQ2
resonance and stuff.
Exp MM Multimode (LPF/Notch/ MIX: blends between LPF/
HPF) output from the Notch/HPF.
classic synthesizer
expander module.
Exp BPF BPF output from the N/A
classic synthesizer
expander module.

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Filter Display Options

You can set display options for the filter to show
frequency, FFT, and phase information, as needed.

Right-click the filter display and choose an option using

the context menu.

Filter Display Menu

The following table describes the available display options:

Option Display Description

Frequency Shows how the filter affects the amplitude of

Response different frequencies in the audio spectrum,
visualized as a graph with frequency on
the horizontal axis and amplitude (gain or
attenuation) on the vertical axis.
Use this view to understand which frequencies
are being boosted, attenuated, or left unaffected
by the filter.

Frequency Re- Combines the filter frequency response curve

sponse & FFT with a real-time FFT (Fast Fourier Transform)
analysis of the audio input. The FFT displays the
actual frequency content of the signal, overlaid
with the filter’s effect.
Use this view to show a dynamic visualization
of both the audio signal spectrum and how the
filter is shaping it in real time, allowing for more
precise adjustments.

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Option Display Description

Phase Re- Shows how the filter affects the phase of

sponse & FFT different frequencies, indicating the degree of
phase shift applied to each frequency in the
signal, alongside the real-time FFT of the audio.
Use this view to understand phase-altering
filters and how they might impact phase-
sensitive tasks like stereo imaging or when
combining multiple signals.

You can quickly cycle through the different display modes by Option-clicking (macOS) or Alt-
clicking (Windows) in the filter display.

Setting Filter Parameters

You can set a range of filter parameters, including the cutoff, resonance, drive, pan, mix, and level. In
addition, different filter types offer a variable parameter depending on context.

Cutoff
Use the CUTOFF knob to set the primary cutoff frequency for the filter (with just a couple exceptions,
such as vowels for formant filters).

Use the (keytrack) switch to offset the cutoff using MIDI notes. With most filter types, one
octave of MIDI corresponds to precisely one octave of filter frequency control.

If the keytrack switch is enabled, this tracks the pitch of the first oscillator (OSC A, OSC B,
or OSC C) that has pitch tracking enabled (including portamento).

If none of the oscillators have pitch tracking enabled, the filter tracks the input MIDI note
number.

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Resonance
Use the RES knob to set the resonance (feedback) of
the filter circuit.

You can graphically adjust the filter cutoff and

resonance (in combination) by clicking and
dragging in the filter display.

This is a quick way to experiment with filter

settings in your sound design.

Graphical Adjustments

Drive
Use the DRIVE knob to increase the gain into the filter
circuit and can impart some coloration (mild distortion)
to the sound.

Right-click the knob and choose Clean Mode in the

context menu to have the filter pre-gain stage the filter
input -24 dB (with a +24 dB boost post-filter).

This reduces saturation and input drive in the filter

models.

Drive Clean Mode

Fat (and Others)

By default, the FAT knob appears when the filter type is MG Low 6 (as part of the Init preset, for
instance). However, this knob changes based on the filter type you select using the menu.

Refer to the table above for details about the knob that appears here.

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Pan
Use the PAN knob to create a cutoff offset for the left and right signals. At the default setting of 50%
(12 o’clock) this knob has no effect. When turned to the left (counter-clockwise) the left channel cutoff
increases, and the right channel cutoff decreases.

When turned to the right (past 12 o’clock clockwise), the opposite happens; the left cutoff decreases
and the right channel cutoff increases.

Mix
Use the MIX knob to control the wet/dry amount for the filter. The default (100%) means 100% wet.

Level
Use the LEVEL slider to adjust the filter output level (in decibels).

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Serum features an advanced mixer that you can use to blend and balance the principal sound sources
in your patch, including the sub oscillator, the three main oscillators (OSC A, B, and C), and the noise
oscillator. In addition, you can include the output from FILTER 1 and 2 in the mix, together with the
output from two internal Serum busses.

In short, the mixer provides you with precise control over the individual elements of your sound. Using
the Serum mixer, you can create complex, layered sounds with ease, adjusting the volume, pan, and
routing of each component to achieve the perfect sound.

Serum Mixer (MIX)

Exploring the Mixer

Click the MIX tab to access the Serum mixer.

Accessing the Serum Mixer (MIX)

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The mixer shows the elements of Serum that you have enabled.

Mixer for the Init Patch

For the Init patch, for instance, only OSC A is enabled and, therefore, this is the only channel enabled in
the mixer. Click the header to enable a channel.

Note that this enables the oscillator or filter throughout

Oscillator Header
Serum.

Each oscillator channel offers the same

controls.

Use the channel menu to specify the signal

routing.

For example, in the illustration below, the

output of OSC A is currently being routed to
the filter module.

However, you could choose to route the

signal to an alternative destination.

Note that, by default, OSC A routes through

FILTER 1, while the OSC B, OSC C, SUB,
and NOISE oscillators route through the
MAIN output by default.
Oscillator Channel Oscillator Channel Menu

Hold the Option/Alt key and drag the oscillator channel label to another oscillator label to
copy the oscillator without modulations.

Hold the Shift-Option or Shift-Alt keys and drag the oscillator channel label to another
oscillator label to copy with modulations.

Dragging from one oscillator channel label to another without any keyboard modifiers swaps
the two oscillators (including modulation assignments).

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The following table describes the signal routing options:

Option Description

Filter Route the signal to the filter module. Use the top knob to set how much of
the signal is sent to FILTER 1 and FILTER 2.

Main Route the signal to the main output. When you choose this option, the
envelope button appears near the bottom left of the channel.
When enabled, the oscillator output level is affected by ENV 1. When
disabled, ENV 1 has no effect on the oscillator output level and it terminates
after the longest release of any of the envelopes. You can use this to make
oscillators appear closer to being free running.
Direct Route the signal to direct output, bypassing the filter and effects sections,
outputting “clean” along with the main output.

Similar to MAIN, when you choose this option, the envelope button
appears near the bottom left of the channel.
None Disable the output of the source (the oscillator, for example).

Sending to the Busses

You can send oscillator signals to BUS 1, BUS 2, or both.

To send a signal to either bus, click and drag the

corresponding BUS knob. To set a specific value, double-
click the knob and type the appropriate value in the field
that appears. Sending to the Busses

Sending a signal through auxiliary effects busses offers multiple advantages, including the following:

• Consistent sound and cohesion

Using a shared bus for effects such as reverb or delay can create a more cohesive sound across the
mix. For example, sending multiple tracks to a single reverb bus can make them sound as if they’re
in the same space, creating a sense of depth and unity.

• More precise control

Auxiliary busses allow you to control the wet/dry balance more precisely, as you can adjust the
send levels from each track to the effect bus. This flexibility makes it easier to blend the effect
subtly or aggressively, depending on the needs of the mix.

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• Parallel processing

Aux busses enable parallel processing, where the dry signal and the processed signal run
simultaneously. This is useful for effects like parallel compression, where you maintain the original
dynamics while adding enhanced processing to the signal.

• CPU efficiency

Instead of applying the same effect to multiple oscillators individually, you can send them to a
single auxiliary bus. This reduces the CPU load since only one instance of the effect is running.

Setting Pan and Levels

You can set the pan and levels for each oscillator as part of creating a balanced and clear audio
experience.

Click and drag the PAN knob left or right, as appropriate. To set
a specific value, double-click the knob and type the appropriate
value in the field that appears.

Use negative values for left and positive values for right.

Similarly, click and drag the level up or down, as needed. To

set a specific value, double-click the control and type the
appropriate value in the field that appears.

You can use panning to effect the following: Setting Pan and Levels

• Create a stereo image — Panning places sound elements across the stereo field (left to right), giving
the mix width and spatial dimension.

By positioning elements in different parts of the stereo field, you create a more realistic and
immersive sound, emulating how we naturally hear sounds around us.

• Prevent clashing — Panning helps separate elements that occupy similar frequency ranges.

For example, if you have two midrange-heavy sound elements, panning them apart reduces the
likelihood of them competing for space and allows each to be heard more clearly.

• Add depth and realism — Proper use of panning mimics the natural placement of sound elements
in a room or on stage. It helps give the listener a sense of depth and positioning, making the mix
feel more dynamic and engaging.

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You can set the levels to control the following:

• Ensure balance — Adjusting levels is essential for achieving a clear and balanced mix.

Setting the volume of each element ensures that the most important parts are prominent while
supporting elements are appropriately audible without overpowering the mix.

• Maintain dynamics — Setting levels effectively preserves the dynamic relationships between sound
elements.

This allows you to better manage contrast between elements.

• Controls focus — Levels can guide listener focuses.

By raising or lowering the volume of certain elements, you can guide the listener’s attention and
shape the overall feel of the sound, making certain parts stand out more prominently while others
remain in the background.

Mixing Filters
You can control how the filter output
integrates into the overall mix.

Important: Even after enabling a filter (by

clicking in the corresponding header), the
filter appears dimmed until you send an
oscillator signal to the filter.

By default, FILTER 1 and FILTER 2 send

through the MAIN output.

Use the channel menu to specify the signal

routing.

Filter Channel Menu Filter Channel Menu

Similar to the filter module, you can graphically adjust the filter cutoff and
resonance (in combination) by clicking and dragging in the filter display.

This is a quick way to experiment with filter settings while mixing!

Filter Adjustments

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The following table describes the signal routing options from the filters:

Option Description

Filter 1 or Filter 2 Route the signal to the other filter, either FILTER 1 or FILTER 2.
Main Route the signal to the main output. When you choose this option, the
envelope button appears near the bottom left of the channel.
When enabled, the oscillator output level is affected by ENV 1. When
disabled, ENV 1 has no effect on the oscillator output level and it terminates
after the longest release of any of the envelopes. You can use this to make
filters appear closer to being free running.
Direct Route the signal to direct output. Similar to MAIN, when you choose this
option, the envelope button appears near the bottom left of the
channel.
None Disable the output of the source (the filter, for example).

Routing to the Busses

You can route filter signals to BUS 1, BUS 2, or both.

To route a signal to either bus, click and drag the

corresponding BUS knob. To set a specific value, double-
click the knob and type the appropriate value in the field
that appears. Routing to the Busses

Setting Pan, Mix and Levels

You can set the pan, mix, and levels for each filter. Click and drag the PAN knob left or right, as
appropriate.

To set a specific value, double-click the knob and type the

appropriate value in the field that appears. Use negative
values for left and positive values for right.

Similarly, click and drag the MIX knob to set the dry/wet
blend of the filter mix.

For most filters, the recommended mix setting is 100% (all

the way to the right).

Note: The MIX knob has no effect for Combs-type filters. Setting Pan, MIX and Levels

Finally, click and drag the level up or down, as needed. To set a specific value, double-click the control
and type the appropriate value in the field that appears.

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Mixing the Busses

You can set the routing and overall
levels for the FX busses.

By default, BUS 1 and BUS 2 route

through the MAIN output.

Use the channel menu to specify

the signal routing.

Click the button to bypass

the corresponding FX module on
the bus.

When enabled, the button

highlights in red to show that the
FX module is being bypassed.

Mixing Busses Filter Channel Menu

The following table describes the signal routing options from the busses:

Option Description

Main Route the signal to the main output.

Direct Route the signal to direct output.
Bus 1 or Bus 2 Route the signal to the other bus, either BUS 1 or BUS 2.

Setting Levels
You can set the level for each bus.

Click and drag the level up or down, as appropriate.

To set a specific value, double-click the control and type

the appropriate value in the field that appears.

Setting Levels

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Setting the Main and Direct Levels

You can set the MAIN and DIRECT levels for the mix.

Click and drag the levels up or down, as appropriate.

To set a specific value, double-click the control and type the

appropriate value in the field that appears.

Click the button to bypass the corresponding FX module

on the main channel.

When enabled, the button highlights in red to show that the FX

module is being bypassed.

Setting Main and Direct Levels

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Serum features an effects section with 13 different FX processors that you can use in any order or
combination, including multiple instances of the same processor. There are also three types of splitter
modules that allow FX processing to be applied to a particular part of the signal.

Serum Effects (FX)

Using the FX Module

Click the FX tab to access the effects module.

Accessing Serum FX (Effects)

An empty rack appears that you can populate with any of the 13 effects modules, in any order.

Click the button (near the top left) to expand the FX rack and list view. Alternatively, press
Option-F (macOS)/Alt-F (Windows) to expand the view.

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This provides more rack space to display modules without scrolling.

FX Rack and List Views (Expanded)

Click the button to revert the FX rack (and list view) back to its original size. Similarly, press
Option-F (macOS)/Alt-F (Windows) to revert the view to the original size.

Selecting a Rack
Serum offers three FX racks: MAIN, BUS 1,
and BUS 2. Each FX rack processes the audio
signal on the corresponding channel.

Click one of the tabs to select the

corresponding FX rack.

Serum FX Racks

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Loading Rack Presets

A quick way to get started is to
load rack presets, available using
the presets drop-down menu.

The preset populates the rack

(including the list view on the left).

At any time, you can initialize an

FX rack by choosing Init as the
factory preset.

FX Presets Menu

The following shows an example FX preset:

Acid Dist Delay Rack Preset

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Adding Modules
Click the button and choose a module in the list
that appears.

Alternatively, you can add a module to the rack by right-

clicking in the rack, choosing Add FX Module, and then
choosing the FX module in the menu that appears.

The module appears in the rack.

After you place an FX module in the rack, all audio

routed to MAIN passes through the module (and then
to the master volume and output).

Note that the signal flow is top to bottom through the

rack.

Adding an FX Module

Module Added to the Rack

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Reordering Modules
To reorder effects, click and drag an effect to the new location in the list view (on the left) or in the rack
view (on the right). A yellow line indicates where the module will land.

Reordering Modules

Copying a Module
You can copy an FX module to create a duplicate of the module on a rack, with or without assigned
modulations.

To copy a module without modulations, Option-drag (macOS) or Alt-drag (Windows) an existing module
to the appropriate location on the rack. A yellow line indicates where the module will land, which is
helpful when placing a module between two existing modules.

Copying a Module

To copy a module with assigned modulations, Shift-Option-drag (macOS) or Shift-Alt-drag (Windows) an

existing module to an empty location on the rack.

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Bypassing a Module
Every FX module features a bypass button that allows you to easily bypass the module. This
button appears to the right of the module both in the list and rack view.

Clicking the button bypasses the module in the signal routing. When enabled, the button highlights in
red to show that the module is being bypassed.

Bypass Effect Button

Bypassing a module is really intended for temporary use. For example, you can use bypass to hear your
sound with and without a given FX (without having to set the MIX knob to 100% dry).

Option-clicking (macOS) or Alt-clicking (Windows) on a bypass button toggles bypass for all FX
on the bus. This also works with the FX bypass buttons on the MIXER page.

Removing a Module
To deactivate an effect, you should generally
remove the module from the rack (you can always
add it back later).

Click the button for the corresponding module

in the list view (on the left).

Remove an FX Module

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Saving a Rack as a Preset

After creating a new custom rack, or modifying an existing rack, you can save the rack as a new preset

Click the button. A dialog appears allowing you to type the rack preset name. By default, the preset
is saved in a standard user location so that Serum can easily find it later.

Exploring FX Rack Operations

Serum makes it easy to manage your FX racks by offering a series of operations that you can quickly
access by right-clicking in the background of the rack.

The following table describes the operations you can perform:

Operation Description

<Select a module> Add a module to the rack.

Cut FX Bus Cut (remove) all modules from the current rack. You can then paste the
modules into another rack.
Use this when you want to move all modules from one rack (such as MAIN)
to another rack (such as BUS 1).
Copy FX Bus Copy all modules from the current rack. You can then paste the modules
into another rack.
Use this when you want to duplicate all modules in one rack (such as MAIN)
in another rack (such as BUS 1).
Paste FX Bus Paste the contents of the rack clipboard (after a cut or copy operation) to
the currently-selected rack.
Clear FX Bus Clear the currently-selected rack. This removes all modules from the rack.
Lock FX Bus Enable this option to have the modules in the selected rack remain in place
when changing presets (no modules will be loaded to that rack).
Note that modulation assignments to module parameters in the locked rack
are cleared when changing presets.
Lock All FX Busses As the name implies, locks all FX busses (in the manner described above).
Load FX Bus Load a user preset rack. Serum displays a dialog allowing you to choose the
appropriate rack.
Save FX Bus Save the current rack as a user preset.

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Modulating FX Parameters
You can modulate most FX parameters, similar to the way you can modulate standard Serum synth
controls.

Click and drag an envelope (ENV) or LFO to the modulation destination.

Assigning to Modulation to an FX Module

The FX rack is a DSP process that operates on the sum output of the synth engine
(rather than per voice). You can think of this as “the effects are monophonic” or “the
effects are like plug-in inserts after Serum.” This is sometimes referred to as paraphonic
behavior, especially in conjunction with the filter effect.

Therefore when playing polyphonic synth parts (strummed chords, for example) keep
in mind that automating FX controls with per-voice mod sources (such as an envelope)
results in the effect parameter modulation being modulated/retriggered by each new
note.

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Exploring FX Module Operations

When working with individual modules in an FX rack, you can load presets, save your current module
settings as a preset, as well as duplicate or remove a module.

Click the button to display the module menu. Note that the color of the button varies depending on
the color of the module. A drop-down menu appears.

Module Menu

The following table describes the operations you can perform:

Operation Description

Factory Load a factory preset for the FX module.

Save FX Preset Save the module configuration as a user preset.
Save as Default Preset Set the current module configuration as the default preset when
adding the same type of module to an FX rack.
Duplicate FX Module Duplicate the module on the rack (with the current module settings).
Remove FX Module Remove the module from the rack.

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Exploring Individual FX Modules

This section describes the controls available of each FX module.

Bode
The BODE module offers an implementation of the Bode frequency shifter, a device that shifts the
frequency of an audio signal by a fixed amount, resulting in a unique sound effect.

Named after electronic music and audio signal processing pioneer Harald Bode, this frequency shifting
can create dissonance, phasing effects, or a sense of movement in sound, which you can creatively
apply to your sound design.

Bode Module

The BODE module offers the following controls:

Control Description

MONO INPUT Enable to route mono input to the module.

SHIFT The percentage of the range to which to apply the pitch shift.
Right-click the knob and choose Retrig in the context menu to have the
module restart the effect for each new note.
RANGE The range of the bode shift.
DIR The direction of the bode shift. Setting to the center causes both channels
to go in opposite directions.
WIDTH Used in conjunction with the DIR knob, WIDTH specifies whether both
Bode channels (up and down) are used, or if only a single channel is used.
DELAY The delay time.
BPM Specifies whether the delay time is synced to the BPM or measured in
Hertz (Hz).
FEED The amount of delay fed back into the Bode shifter, which can produce
pitched delays.
BALANCE The delay input mix between a down and up shifted signal.
BLUR Use to create chorus and wow/flutter effects.
MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

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Chorus
The CHORUS module offers a four-voice chorus effect, with two left and two right chorus taps.

Chorus Module

The CHORUS module offers the following controls:

Control Description

RATE The rate of the chorus. The units depend on the BPM setting. When BPM is
on, the RATE knob snaps to musical time (from 8 bars to 1/32nd note).
When BPM is off, the RATE knob is in Hertz (Hz), between 0 Hz and 20 Hz.
BPM Specify whether the chorus is synced to the host BPM. See the RATE knob
(above) for more information.
DELAY 1 The amount of delay (in milliseconds) between the dry signal and the first
stereo pair of chorus voices.
DELAY 2 The amount of delay (in milliseconds) between the dry signal and the second
pair of chorus voices.
DEPTH Specifies how much the chorus LFO modulates the delay times described
above (how much pitch warble occurs).
FEEDBACK The feedback amount of the chorus voices (how much of the chorus voice
output appears back at the input of the chorus module). This creates a more
pronounced “ringing” to the chorus.
LPF/HPF The cutoff frequency in Hertz (Hz) of the low pass/high pass filter after the
chorus wet effect. This is useful for a more (or less) “warm doubling” of the
signal. Click the label to toggle between LPF and HPF.
MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

Compressor
The COMPRESSOR module reduces the volume of loud sounds or amplifies quiet sounds, thereby
reducing or compressing the dynamic range of an audio signal.

Compressor Module

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The COMPRESSOR module offers the following controls:

Control Description

MODE The compressor mode, either SINGLE or MULTIBAND. The mode

determines how the compressor processes audio signals.
SINGLE — Select to configure the module as a single-band compressor. This
causes the compressor to affect the entire frequency spectrum of the audio
signal as one unified band. In other words, it applies compression uniformly
across all frequencies.
Single-band compressors are often used for overall dynamic control of a
track or mix. They are simpler and more straightforward, making them ideal
for general-purpose compression.
However, when a single-band compressor is triggered by a loud frequency, it
compresses the entire signal. This can cause other frequencies, such as mids
and highs, to be compressed as well, even if they don’t need it, leading to
less precise dynamic control.
MULTIBAND — A multiband compressor divides the audio signal
into multiple frequency bands, allowing you to compress each band
independently. This provides more precise control over the dynamics of
different parts of the frequency spectrum.
Select this option to make the compressor become a multiband upwards/
downwards compressor. This is an extreme setting, but you may find a use
for it.
The individual bands are separately user-adjustable, and you can assign
modulations using the modulation matrix. This is useful for side-chaining just
the low end out of the way of a kick or bass.
THRESH The threshold (in dB) for the compression to start engaging. A setting of 0
equals 0 dB (no compression, unless the input signal is overloaded); a setting
of 100% equals -120 dB (almost always compressing).
Typically, you would set this to around the middle of the range (for example,
around -12 dB), but the setting is dependent on your input signal strength
and the amount of compression you want.
RATIO The strength of the gain reduction. Typical compression is between 2:1 and
4:1. If you set the compression knob to maximum, Limit appears.
This offers a completely different DSP circuit (a true peak limiter and not
a compressor); therefore, the other controls behave differently when the
limiter is engaged. Specifically, the attack time range changes to 0-10ms and
the makeup gain range changes to 0-36dB.
Note: Setting the ratio to Limit can introduce latency. Right-click the knob
and choose Limiter Latency Comp in the context menu to have the module
report this latency to the host.

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Control Description

ATTACK The amount of time in milliseconds for the gain reduction to engage.
A longer (slow) attack is useful for letting some signal through before the
gain reduction takes place, resulting in a “punch,” “snap,” or “bite” (sounds are
hard to describe using language!).
A shorter/faster attack tames peaks more completely.
RELEASE The amount of time for the gain reduction to be removed.
GAIN The amount of makeup gain. This is a good way to boost quiet signals. The
control allows for approximately 30dB of boost for the compressor and
36dB for the limiter so be careful (that’s a large amount of gain). Basically, a
little can go a long way.
X-LOW (Enabled when MULTIBAND is selected) Sets the low crossover for the
multiband split.
BELOW (Enabled when MULTIBAND is selected) Sets the compression ratio below
the threshold.
X-HIGH (Enabled when MULTIBAND is selected) Sets the high crossover for the
multiband split.
H (Enabled when MULTIBAND is selected) Sets the high band gain.
M (Enabled when MULTIBAND is selected) Sets the mid band gain.
L (Enabled when MULTIBAND is selected) Sets the low band gain.
MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

Convolve
The CONVOLVE module allows you to apply the impulse response of a signal you select (representing
the characteristics of a room’s reverb or a specific filter) to your sound design.

The most common use is to create a convolution reverb, where the impulse response of a real acoustic
space (such as a concert hall) is convoluted with your audio signal to simulate how that signal would
sound if played in that space. This allows for highly realistic and complex reverb effects.

You can also use the CONVOLVE module to blend sounds in unique ways, applying an effect that alters
your sound in a manner different from simple filtering or other modulation techniques.

Convolve Module

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The CONVOLVE module offers the following controls:

Control Description

IMPULSE Click to choose from a menu of impulse responses. Use the < > arrows to
advance through the modes without having to open the menu.

You can load impulse responses from outside the Serum 2 Presets
folder by dragging and dropping the files on the IR display or selecting Load
IR from the context menu.
If you do this, the option to Embed in Preset appears in the menu, and an
embed icon appears at the top right of the IR display. This allows you to
embed the impulse response into the preset, similar to what you can do with
oscillators.
SIZE The size with which to stretch or contract the impulse.
TONE Use to filter the impulse.
ϕ MIN The convolution minimum phase. This converts the IR to a minimum-phase
representation, keeping the frequency response unchanged and eliminating
echoing.
PRE-DLY The convolution pre-delay. This offsets the impulse in time.
BPM Specifies whether the pre-delay is synced (BPM or millisecond based.
ATTACK The convolution attack. Use this to fade in the impulse.
DECAY The convolution decay. Use to shorten the impulse.
DAMP Use to shorten the high frequency of the impulse.
IR GAIN The impulse volume.
MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

Delay
The DELAY module records an input signal and then plays it back after a period of time. The delayed
signal may be played back multiple times, or fed back into the recording, to create the sound of a
repeating, decaying echo.

Delay Module

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The DELAY module offers the following controls:

Control Description

MODE The type of delay, from among the following:

NORMAL — Specifies a standard stereo delay with independent left and
right channels/times.
PING-PONG — Sets the outputs of the left and right delays to feed into one
another.
TAP-> DELAY — Sets both delays to mono and in series, causing the
left signal to fire once with no feedback (tap) followed by the right signal
operating as a typical delay (feedback is applied here).
Select the High Quality option to render the output of the module in higher
quality.
Delay Times The delay times.
There are two settings available for both the left and right channels. The
upper input is the base delay time for the channel. The lower box is a (scalar)
offset for the delay time you set above.
For instance, a value of 1.1 means that the corresponding delay time sounds
at 110% of its value. Dragging the lower inputs displays Trip or Dot when
you reach 133% (1.333) and 150% (1.5) respectively. This allows you to
quickly set triplet or dotted values for the delay times.
BPM/MS Specifies whether the delay times are in tempo-based units (quarter note,
for example) or in milliseconds.
Enable to have the right-channel delay times link with (kept the same as) the
LINK left channel delay times.
FEEDBACK The amount of the delayed signal appearing back at the input of the delay.
This is useful for controlling how many delay repeats are audible.
FREQ (Frequency) The filter cutoff frequency (in Hertz) for the delay filter.
Q (Resonance) The bandwidth for the delay filter (how much low pass and high pass are
applied).
Technically, this is the opposite of a standard Q control, where a larger Q
value typically signifies a narrow filter bandwidth. However, in this case, a
maximum value means minimum filtering/maximum bandwidth.
MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

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Manipulating the Delay Filter

In addition to using the FREQ and Q knobs, you can manipulate the delay filter using your mouse.

By default, the delay filter appears like this.

Click the drag in the display to set the frequency

and Q simultaneously.

Double-click the display to toggle a real-time

frequency overlay.

Distortion
The DISTORTION module offers 13 types of distortion, including two dual-waveshaper modes that
allow you to create your own custom distortion.

Distortion Module

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The DISTORTION module offers the following controls:

Control Description

MODE Click to choose from a menu of distortion types (Tube, by default). You can
use the < > arrows to advance through the modes without having to open
the menu.
OFF/PRE/POST A switch to enable filtering, which you can set to either pre-distortion (PRE)
or post-distortion (POST).
TYPE The filter type for the distortion module. Drag the red control between left
and right to morph from low pass to bandpass to high pass.
FREQ The cutoff frequency for the filter (when the filter is enabled). Double-click
the field to display a text box, allowing you to enter a frequency value.
Right-click the knob and choose Key Track in the context menu to have
frequency respond to the pitch of the note played. With Key Track disabled,
the frequency is fixed regardless of the key played.
With Key Track enabled, the frequency changes in proportion to the pitch
of the note played (higher-pitched notes increase the frequency).
Q The resonance for the filter (when the filter is enabled). Double-click the
field to display a text box, allowing you to enter a resonance value.
You can set a high value to create squelchy feedback. Typically, lower values
are more common.
DRIVE Generally, the gain boost for the distortion, with the following exceptions:

• With Downsample filter type, the DRIVE knob controls the sample rate
reduction amount.

• With X-Shaper and X-Shaper (Asym) modes, the DRIVE knob affects a
morph between the two waveshapes.

You can also set the drive by dragging up or

down in the graphic display.

MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

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Understanding X-Shaper (Dual Waveshaper) FX Modes

The X-Shaper is a dual crossfading waveshaper. Selecting X-Shaper in the distortion menu causes Edit
A and Edit B buttons to appear directly below the menu.

Clicking either button displays a pop-up “X-Y” graph editor for the respective waveshaper. In both cases,
the X (horizontal) axis represents the input level, and the Y (vertical) axis represents the corresponding
remapped output level for an input level.

The DRIVE knob, described above, controls the blend between the two waveshaping graphs (the
DRIVE knob at 0% presents waveshaper A while 100% presents waveshaper B).

Note that X-Shaper is a symmetric waveshaper, with the lower-left point on the graph representing
silence (-INF dB for input and output). Similarly, the top-right point represents the highest level (0 dB for
input and output).

In contrast, X-shaper (Asym) is an asymmetric waveshaper. In this case, the middle of the graph
represents silence (-INF dB input and output), the top-right represents the highest positive value to the
signal, and the lower-left represents the highest possible negative value.

Asymmetric distortion allows you to bring out even-order harmonics that are not typically found in a
standard symmetric distortion (such as clipping). This is often the case in guitar amps; one pole distorts
(for example, fatline) while the other pole remains relatively undistorted.

Equalizer
The EQUALIZER module offers two-band parametric control.

Equalizer Module

You can set the type of each of the two bands using the corresponding three-state switches. The left
band offers low-frequency (LF) adjustment and enables low shelf, peaking, or high pass filtering. The
right band offers high-frequency (HF) adjustment and enables high shelf, peaking, or low pass filtering.

The EQUALIZER module offers the following controls:

Control Description

FREQ (L) The frequency (in Hz) for the low EQ band.
Q (L) The Q (resonance) for the low EQ band.
GAIN (L) The gain boost/cut (in dB) for the low EQ band. This knob has no effect if
you selected High Pass as the low EQ band type.

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Control Description

FILTER TYPE Click the icons to select a Shelf, Peak, or High Pass filter type (on the left)
and Shelf, Peak, or Low Pass filter type (on the right).
FREQ (R) The frequency (in Hz) for the high EQ band.
Q (R) The Q (resonance) for the high EQ band.
GAIN (R) The gain boost/cut (in dB) for the high EQ band. This knob has no effect if
you selected Lowpass as the high EQ band type.
LEVEL The output level of the module (in decibels).

Filter
The FILTER module operates identically to the per-voice synth filter found on the main OSC tab, except
that in this case, it runs as a master effect.

Filter Module

The FILTER module offers the following controls:

Control Description

TYPE Click to choose from a menu of filter types (MG Low 6, by default). You can
use the < > arrows to advance through the filter types without having to
open the menu.

See “Filter Types and Var Parameter Functions” for more information about
the available filter types.
CUTOFF The primary cutoff frequency for the filter (with just a couple exceptions,
such as vowels for formant filters).
TIP: You can recreate certain paraphonic vintage synth behaviors by
applying an envelope to this knob.
Right-click the knob and choose Key Track in the context menu to have
cutoff frequency respond to the pitch of the note played. With Key Track
disabled, the cutoff frequency is fixed regardless of the key played.
With Key Track enabled, the cutoff frequency changes in proportion to the
pitch of the note played (higher-pitched notes increase the cutoff frequency.
RES The resonance (feedback) of the filter circuit.

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Control Description

DRIVE The gain into the filter circuit. The setting can impart some coloration (mild
distortion) to the sound.
Right-click the knob and choose Clean Mode in the context menu to have
the filter pre-gain stage the filter input -24 dB (with a +24 dB boost post-
filter).
FAT/FREQ/MORPH/ This is a variable knob with different functions depending on the selected
LP FRO/HP FRO/ filter type.
HL WID/LP FRO/
DB +/-/SPREAD/ For instance, with “dual” filters, the VAR knob controls the second filter
DAMP/BOEUF/ cutoff frequency.
THRU/FORMNT/
WIDTH/COMBFRO/
SCREAM/STAGES/
SMOOTH/PAIN/
FRO2
PAN A cutoff offset for the left and right signals. At the default setting of 50% (12
o’clock) this knob has no effect. When turned to the left (counter-clockwise)
the left channel cutoff increases, and the right channel cutoff decreases.
When turned to the right (past 12 o’clock clockwise), the opposite happens;
the left cutoff decreases and the right channel cutoff increases.
MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

You can graphically adjust the filter cutoff and resonance (in
combination) by clicking and dragging in the filter display.

This is a quick way to experiment with filter settings in your sound

design.

Right-click in the display to access a menu allowing you to choose Graphical Adjustments
display options for the filter.

The following table describes the available display options.

Option Display Description

Frequency Shows how the filter affects the amplitude of

Response different frequencies in the audio spectrum,
visualized as a graph with frequency on
the horizontal axis and amplitude (gain or
attenuation) on the vertical axis.

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Option Display Description

Frequency Combines the filter frequency response curve

Response with a real-time FFT (Fast Fourier Transform)
& FFT analysis of the audio input.
The FFT displays the actual frequency content
of the signal, overlaid with the filter’s effect.

Phase Shows how the filter affects the phase of

Response different frequencies, indicating the degree of
& FFT phase shift applied to each frequency in the
signal, alongside the real-time FFT of the audio.

You can quickly cycle through the different display modes by Option-clicking (macOS) or Alt-
clicking (Windows) in the filter display.

Flanger
The FLANGER module works by cyclically varying phase shift into one of two identical copies of a signal
and then recombining them.

Flanger Module

The FLANGER module offers the following controls:

Control Description

RATE The rate of the flanger. The units depend on the BPM setting. When BPM
is on, the RATE knob snaps to musical time (from 8 bars to 1/32nd note).
When BPM is off, the RATE knob is in Hertz (Hz), between 0 Hz and 20 Hz.
BPM Specifies whether the flanger sweep is synced to the host BPM. See the
RATE knob (above) for more information.
DEPTH Specifies how much the flanger LFO influences the sound, in other words,
how much (or deep) the flanger operates.
FEEDBACK The feedback amount of the flanger circuit, which makes the effect more
pronounced (“ringing”).

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Control Description

PHASE The stereo phase offset for the LFO influence over the flanger (the left
flange and right flange offset). A setting of 0% sets both left and right to the
same frequency.
A setting of 50% represents 180 degrees, meaning that the left and right
have opposite frequencies. In this case, the flanger sweep “rises” on the left
while “falling” on the right, or vice versa.
MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

Hyper/Dimension
The HYPER/DIMENSION module is a micro-delay chorus with a variable number of voices (1-7). In
addition you can configure the Hyper/Dimension effect to retrigger on every MIDI note, which adds to
the potential simulation of a unison.

To conserve CPU, consider using the HYPER effect as an alternative to high unison settings.

Hyper/Dimension Module

The HYPER module offers the following controls:

Control Description

RATE The speed at which the various hyper voices oscillate sharp/fat in pitch.
UNISON The number of chorus voices. If you only want to use the DIMENSION
effect and not the HYPER effect, set the UNISON to 0.
DETUNE The amount/depth of the hyper voice oscillations (sharp/fat in pitch).
RETRIG When turned on, resets all hyper voices to start over from a zeroed-pitch
offset.
This provides a laser-like zap effect for each note-on event. You might use
this on certain monophonic patches, for example.
MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

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The DIMENSION effect is a pseudo-stereo effect consisting of four delay lines summed out-of-phase
and slowly amplitude-modulated to provide a subtle amount of motion to the effect. This is useful for
adding a perceived width to an otherwise mono signal.

The DIMENSION module offers the following controls:

Control Description

SIZE Adds an extra layer of phased delays.

MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

Phaser
The PHASER module filters a signal by creating a series of peaks and troughs in the frequency
spectrum.

Phaser Module

The PHASER module offers the following controls:

Control Description

RATE The rate of the phaser. The units depend on the BPM setting. When BPM
is on, the RATE knob snaps to musical time (from 8 bars to 1/32nd note).
When BPM is off, the RATE knob is in Hertz (Hz), between 0 Hz and 20 Hz.
BPM Specifies whether the phaser sweep is synced to the host BPM. See the
RATE knob (above) for more information.
POLES The number of stacked phaser poles.
DEPTH Specifies how much the phaser LFO influences the sound.
DEPTH 2 The offset between phaser stages.
FREQ The base frequency for the phaser effect.
FEEDBACK The feedback amount of the phaser circuit. A higher setting makes the effect
more pronounced (“ringing”).
PHASE The stereo phase offset for the LFO influence over the phaser (left flange
and right flange offset). A setting of 0% sets both left and right to the same
frequency.
A setting of 50% represents 180 degrees, with left and right at opposite
frequencies (in other words, the phaser sweep “rises” on the left while
“falling” on the right, or vice versa.

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Control Description

MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

Reverb
The REVERB module offers a plate and hall reverb, using a modified version of the Tal Reverb algorithm
(courtesy of Togu Audio Line).

Reverb Module

The REVERB module offers the following controls:

Style Control Description

TYPE Click to choose from a menu of reverb types (PLATE, by default).

You can use the < > arrows to advance through the reverb types
without having to open the menu.
PLATE LO CUT Suppress low frequencies from the reverb. 0% means no effect
on lows, 100% means no lows at all.
HI CUT Suppress high frequencies from the reverb. 0% means no effect
on highs, 100% means no high frequencies at all.
SIZE The length of the reverb.
PRE-DLY The offset time for the reverb.
DAMP An additional high-frequency cut for the reverb.
The knob controls how fast this high-frequency attenuation
occurs. 0% mean no damping, 100% means maximum damping.
WIDTH Expand or collapse the stereo width of the reverb. 100% means
maximum width.
HALL LO CUT Suppress low frequencies from the reverb. 0% means no effect
on lows, 100% means no lows at all.
HI CUT Suppress high frequencies from the reverb. 0% means no effect
on highs, 100% means no high frequencies at all.
SIZE The room size (reverb time + dimension).

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Style Control Description

PRE-DLY The amount of time (in milliseconds) before reverberation

occurs. Using pre-delay allows you to give the impression that a
sound is close to you but in a large room.
You can also use it to separate your transient from the reverb or
create a delay-like echo.
DECAY The amount of decay (in milliseconds).
SPIN RATE Set the speed of the LFO used to modulate time differences.
HALL (cont.) SPIN DEPTH Modulate time differences with an LFO to create a sense of
movement within the reverb.
VINTAGE LO CUT Suppress low frequencies from the reverb. 0% means no effect
on lows, 100% means no lows at all.
HI CUT Suppress high frequencies from the reverb. 0% means no effect
on highs, 100% means no high frequencies at all.
SIZE The length of the reverb.
PRE-DLY The amount of time (in milliseconds) before reverberation
occurs. Using pre-delay allows you to give the impression that a
sound is close to you but in a large room.
You can also use it to separate your transient from the reverb or
create a delay-like echo.
ER SIZE The length of the early reflection part of the reverb.
DECAY The amount of decay (in milliseconds).
DAMP The speed at which high frequencies decay.
DIFF A The diffusion of the reverb.
DIFF B Dampen the diffusion stage of the reverb.
CHORUS The top value sets the speed that the reverb is modulated.
The bottom value sets the pitch depth that the reverb is
modulated.
NITROUS LO CUT Suppress low frequencies from the reverb. 0% means no effect
on lows, 100% means no lows at all.
HI CUT Suppress high frequencies from the reverb. 0% means no effect
on highs, 100% means no high frequencies at all.
SIZE The length of the reverb.
PRE-DLY The offset time for the reverb.
FEEDBACK The amount of reverb fed back into the input signal.
DIFFUSION The diffusion of the reverb.

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Style Control Description

MODE The nitrous mode, from among the following:

• Space
• Marble
• Rectangle
• Hexagon
• Box
NITROUS CHORUS The top value sets the speed that the reverb is modulated.
(cont.)
The bottom value sets the pitch depth that the reverb is
modulated.
BASIN LO CUT Suppress low frequencies from the reverb. 0% means no effect
on lows, 100% means no lows at all.
HI CUT Suppress high frequencies from the reverb. 0% means no effect
on highs, 100% means no high frequencies at all.
SIZE The length of the reverb.
PRE-DLY The offset time for the reverb.
FEEDBACK The amount of reverb fed back into the input signal.
CHORUS The top value sets the speed that the reverb is modulated.
The bottom value sets the pitch depth that the reverb is
modulated.
MIX The wet/dry amount for the effect, from 0 (100% dry) to 100
(100% wet).
LEVEL The output level of the module (in decibels).

Splitter L/H
The SPLITTER L/H module divides the audio signal into distinct low and high-frequency bands,
enabling you to design and apply dedicated FX racks for each band independently.

This setup provides precise control over your sound, allowing for tailored processing that enhances both
the low-end punch and high-end clarity.

Splitter L/H Module

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When using this module, you can build two separate racks, one to handle the LOWS and another to
process the HIGHS. The list view (on the left) shows both racks. The rack view, however, only shows the
currently-selected rack. Click the LOWS or HIGHS panel to display the corresponding rack.

Splitter L/H Module Example

The SPLITTER L/H module offers the following controls:

Control Description

LOWS Right-click in the panel and choose an FX module to add using the menu
that appears. Continue doing this until you finish building the low-end rack.
Each time you add a module, it appears below the SPLITTER L/H main
module.
Note the bypass button in the LOWS panel. Enabling this bypasses the low-
end rack.
SPLIT FREQ The crossover frequency for the low and high bands.
HIGHS Right-click in the panel and choose an FX module to add using the menu
that appears. Continue doing this until you finish building the high-end rack.
Each time you add a module, it appears below the SPLITTER L/H main
module.
Note the bypass button in the HIGHS panel. Enabling this bypasses the
high-end rack.
LEVEL The output level of the module (in decibels).

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Splitter L/M/H
The SPLITTER L/M/H module divides the audio signal into low, mid, and high-frequency bands,
offering even greater flexibility than the SPLITTER L/H module. This configuration enables you to
design and apply dedicated FX racks for each band independently, allowing for fine-tuned control over
your sound.

With the addition of the MIDS panel, you gain the ability to shape and process the critical midrange
frequencies separately, ensuring that elements like vocals, guitars, and synths stand out or blend
seamlessly. This setup provides precise control, enhancing the low-end punch, midrange presence, and
high-end clarity, for a more refined and impactful mix.

Splitter L/M/H Module

When using this module, you can build three distinct racks, one to handle the LOWS, one for the MIDS,
and another to process the HIGHS. The list view (on the left) shows all three racks. The rack view,
however, only shows the currently-selected rack. Click the LOWS, MIDS, or HIGHS panel to display the
corresponding rack.

Splitter L/M/H Module Example

The SPLITTER L/M/H module offers the following controls:

Control Description

LOWS Right-click in the panel and choose an FX module to add using the menu
that appears. Continue doing this until you finish building the low-end rack.
Each time you add a module, it appears below the SPLITTER L/M/H main
module.
Note the bypass button in the LOWS panel. Enabling this bypasses the low-
end rack.

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Control Description

SPLIT FREQ The crossover frequency for the low and mid bands.
MIDS Right-click in the panel and choose an FX module to add using the menu
that appears. Continue doing this until you finish building the low-end rack.
Each time you add a module, it appears below the SPLITTER L/M/H main
module.
Note the bypass button in the MIDS panel. Enabling this bypasses the mid-
end rack.
SPLIT FREQ The crossover frequency for the mid and high bands.
HIGHS Right-click in the panel and choose an FX module to add using the menu
that appears. Continue doing this until you finish building the high-end rack.
Each time you add a module, it appears below the SPLITTER L/M/H main
module.
Note the bypass button in the HIGHS panel. Enabling this bypasses the
high-end rack.
LEVEL The output level of the module (in decibels).

Splitter MS
The SPLITTER M/S module divides the audio signal into mid and side bands. This configuration enables
you to design and apply dedicated FX racks for each band independently, allowing for precise control
over the central and spatial elements of your sound.

Use it to enhance focus and presence by processing the mid channel, or to control depth and width by
processing the side channel, giving you a powerful tool for shaping your mix.

Splitter M/S Module

When using this module, you can build two separate racks, one to handle the MID band and another to
process the SIDE band. The list view (on the left) shows both racks. The rack view, however, only shows
the currently-selected rack. Click the MID or SIDE panel to display the corresponding rack.

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Splitter M/S Module Example

The SPLITTER M/S module offers the following controls:

Control Description

MID Right-click in the panel and choose an FX module to add using the menu
that appears. Continue doing this until you finish building the mid-band rack.
Each time you add a module, it appears below the SPLITTER M/S main
module.
Note the bypass button in the MID panel. Enabling this bypasses the mid-
band rack.
SIDE Right-click in the panel and choose an FX module to add using the menu
that appears. Continue doing this until you finish building the side-band
rack.
Each time you add a module, it appears below the SPLITTER M/S main
module.
Note the bypass button in the SIDE panel. Enabling this bypasses the side-
band rack.
LEVEL The output level of the module (in decibels).

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Utility
The UTILITY module offers a series of “utility” functions including polarity inversion, basic low and high
pass filters, stereo width and balance, and more.

Utility Module

The UTILITY module offers the following controls:

Control Description

POLARITY INV Invert the polarity of the audio signal on the left and right channel of the
signal respectively.
LPF The low pass filter.
HPF The high pass filter.
MONO BASS/FREQ Enable for mono bass, which forces frequencies below the threshold (set
using the FREQ control) to be monophonic.
WIDTH The stereo width.
PAN The stereo balance.
MIX The wet/dry amount for the effect, from 0 (100% dry) to 100 (100% wet).
LEVEL The output level of the module (in decibels).

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Serum offers advanced options for sound modulation, allowing you to create dynamic sounds with
motion. Modulating sound in Serum principally involves working in the following three areas:

1. Envelopes

2. LFOs

3. Modulation Matrix

Serum Sound Modulation

Using Envelopes
The Envelopes module offers four modulation sources, labeled ENV 1, ENV 2, ENV 3, and ENV 4. The
following shows the Envelopes area of Serum.

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Serum Envelopes

Configuring Envelopes
Select an envelope by clicking the
corresponding envelope tab.

Modify the envelope directly using your

mouse.

Alternatively, adjust the ATK (attack),

HOLD, DEC (decay), SUS (sustain), and
REL (release) knobs to change the envelope
parameters.

Click the (lock) button to auto-

normalize the zoom.

Alternatively, drag the mouse through the

Envelope Operations
zoom slider to manually zoom the envelope
display.

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Lock Button Description

Locked The envelope always zooms to perfectly fill the display area. This means that
adjusting envelope times simply changes how much time is represented on
the ruler scaling below the envelope.
Unlocked Allows you to zoom in and out of the envelope by dragging up and down in
the zoom area directly below the Lock button.

See “Modifying Envelopes” later in this chapter for details about changing envelope shapes.

You can use all four envelopes, though ENV 1 is considered special within Serum because it is
used with the amplifier, controlling the output volume of each voice. You can still use ENV 1,
however, assigning it to any parameter as you would the other envelopes.

When you select ENV 2, ENV 3, or ENV 4, the envelope of ENV 1 is faintly visible (in gray) in
the background.

Inverting the Legato Setting

When the main LEGATO switch is enabled, envelopes do not retrigger if a second note is played while
a first note is still held. You can invert this option to force an envelope to always trigger at note on, even
when legato is enabled.

To do this, right-click the envelope graph and choose Legato Inverted in the context menu.

Setting Envelope Parameter Units

You can choose to alter values in milliseconds or in subdivisions of a note by clicking (MS or
BPM).

When you switch from MS to BPM, Serum calculates the nearest subdivision to the millisecond value
for each control based on host tempo.

Setting the Envelope Verticals

You can select whether the vertical lines that appear in the graph background are placed at time (ms) or
beat intervals.

Right-click on the graph and select either Time or Beats in the Grid sub-menu.

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Modifying Envelopes
You can modify envelope shapes either by setting values using the knobs in the envelope window, or by
manipulating the envelope waveform directly.

To modify an envelope directly, click the

corresponding envelope tab, such as ENV 2,
ENV 3, or ENV 4 and graphically adjust the
envelope points using your mouse.

Alternatively, adjust the respective knob

settings using your mouse.

Important: Remember that ENV 1 is a special

envelope in Serum (it controls the output
volume) and is therefore always active.

Graphical Envelope Edits

You can modify the following envelope parameters using the knobs and directly on the graph:

Control Description

ATK Attack. The time for the initial run-up from start to peak, beginning with the
note on event.
HOLD Hold. The time that the envelope stays at full volume before entering the
decay phase.
DEC Decay. The time for the subsequent run-down from the attack level to the
designated sustain level.
SUS Sustain. The level during the main sequence of the sound’s duration, until
the note off event.
REL Release. The time for the level to decay from the sustain level to zero after
the note off event occurs.

You can modify the following parameters

directly using your mouse (only).

• Attack curve

• Decay curve

• Release curve
Curve Adjustments

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Assigning an Envelope to a Control

You can assign an envelope
to a control (such as a knob),
causing the envelope to
modulate the control.

For example, you might

choose to have an envelope
modulate the wavetable
position (WT POS) setting of
OSC A.

To do this, click and drag the

ENV 1 tab to the WT POS
knob in the OSC A panel.

As you are dragging, notice

that an ENV 1 label hovers
next to the mouse pointer.

The pointer adds a + sign as

you hover over an assignable
knob (in this case, the WT
POS knob).

The + sign indicates that

you are over a valid mod
destination.
Assigning ENV 1 to WT POS
When you release the mouse
button, Serum automatically
makes the connection causing ENV 1 to now affect the OSC A wavetable position.

Right-click an envelope tab to bypass and

remove destinations assigned to the
envelope.

Bypass and Remove Assignments

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Using LFOs
Serum offers ten low frequency oscillators (LFO) that each feature a set of independent controls. The
following shows the LFO area of Serum.

Serum LFOs

Note: When you initialize a patch, only LFO 1 to LFO 6 are visible. LFO 7 to LFO 10 becomes visible
after you use (assign) LFO 6.

Configuring LFOs
Select an LFO by clicking
the corresponding LFO tile.

Modify the LFO graph

directly using your mouse.

Change tools to get

different drawing results.

Fine-tune using the LFO

Editor, if needed.

Adjust knobs and controls

LFO Operations
to change various parameters.

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Note that the settings are independent for each LFO.

To copy all LFO settings from one LFO to another, Option-click-drag (macOS) or Alt-click-drag
(Windows) an LFO title to another.

For example, to copy all the LFO 1 settings to LFO 2, Option/Alt-click-drag the LFO 1 tab to
LFO 2.

Drawing an LFO Graph

Serum offers a set of tools to help you create LFO graphs using your mouse.

LFO Graph Tools

Note that each tool relies on the current grid setting. The following table describes the LFO drawing
tools available:

Type Tool Use to ...

Point Manipulate points in the graph, including adding new points,

moving points, deleting points, and adjusting curves (between
main points).
Flat Add flat lines between points, based on the current grid size.
1

Ramp Up Add ramp ups between points, based on the current grid size.

Ramp Down Add ramp downs between points, based on the current grid size.

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Modifying LFOs
When modifying points on an LFO graph, you can do the following:

Action Task

Double-click Add or remove points.

Shift-click Draw steps at the grid size (step sequencer).
Option-click-drag a point (macOS) Snap the point to the grid size.
Alt-click-drag a point (Windows)
Option-click-drag any curve point Move all curve points at once.
(macOS)
Alt-click-drag any curve point
(Windows)
Click-drag on the background Select multiple points.
Cmd-click-drag a point (macOS) Select multiple points for relative movement. Rainbow
colors appear on the points.
Ctrl-click-drag a point (Windows)
Dragging them makes closer points move more, and
further points move less.
Ctrl-click (macOS) Display a context menu showing additional features,
such as setting the segment shape for Shift-click,
Right-click (Windows) removing all selected points, or assigning the start or
loopback points.
Shift-Cmd-click (macOS) Set the point as the loopback position (or the very last
point if you intend no loopback position).
Shift-Ctrl-click (Windows) on a point
(in Envelope mode) This is simply a shortcut to avoid the menu.

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Modifying LFO Controls

The LFO module features a complete set of controls that you can use to set the LFO type, LFO mode,
BPM, grid size, and other options. The following table explains each of the LFO controls:

Control Description

TYPE The LFO type, from among the following:

• Normal
• Path
• Chaos: Lorenz
• Chaos: Rossler
• S&H
MODE (Retrig) Specifies how the LFO behaves when a new note is played.

• FREE — The LFO follows the host clock and ignores note timing.
• RETRIG — Retriggers the LFO, causing the LFO to start with a new
note.
Use this setting when you want the LFO to always have the same
timing with new notes.

• ENVELOPE — Similar to RETRIG however the LFO plays through a

single cycle before stopping.
It’s possible to loop a segment of the LFO while in envelope mode
using the loopback point, accessible by Ctrl-clicking (macOS) or right-
clicking (Windows) a point and choosing Set Loopback Point Here.

This causes the LFO to play through, then cycle back to the selected
loopback point.
MONO Select whether the LFO is monophonic or polyphonic.
By default, LFOs are polyphonic allow independent modulation for each
voice. With MONO enabled, the same modulation is applied to all voices.
SHAPE Displays a pop-up menu allowing you to load an LFO preset.
Note that this overwrites the current LFO graph. The menu also offers the
ability to save the current LFO graph as a user-defined preset.
DIRECTION The direction of the LFO, from among the following:

• Forward
• Reverse
• Ping Pong

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Control Description

GRID The grid size of the LFO graph. The visual grid background in the LFO graph
changes as you adjust this setting.
Double-click the horizontal or vertical grid box and specify a number to set a
corresponding grid.
The grid is helpful when Alt-clicking (to snap points) or Shift-clicking (to draw
step segments) on the LFO graph. This allows you to align modulation to
the rhythm of your production, or create arpeggiator-like pitch modulations.
HOST Specifies whether the LFO is always synced to the global song position.
When BPM is enabled, the HOST switch determines whether the LFO
playback position “jumps” if you change the LFO rate.
When HOST is enabled, the phase is “anchored” to the host transport
position. For example, when changing the rate from ¼ note to 1 bar, the
phase may jump to have the playback properly fixed to the bar cycle.
BPM/HZ Set the time value to snap to song tempo-based units (1/4 note, 1/8 note,
and so on) or Hertz (free time).
RATE The playback speed of the LFO. This determines the amount of time
represented on the LFO graph area.
The LFO rate is in beat-synced units by default (when BPM is enabled) but
can also be set to a frequency in Hertz (when HZ is enabled).
When BPM is selected (see above), right-click the RATE knob and choose
Swing in the context menu to add swing to the LFO (using the SWING
setting above the keyboard).
When HZ is selected, right-click the RATE knob and choose 10x in the
menu to have the range of the rate control (in Hz) multiplied by a factor of
10, allowing for faster LFO rates.
TRIP/DOT Set triplet and dotted time on the rate control respectively.
These are useful for avoiding triplet or dotted times when automating the
LFO rate, that is, for avoiding dotted and triplet times when you know you
want evenly beat-divisible time.
RISE The amount of time for the LFO graph shape to have influence over the
LFO output.
The LFO begins with a fixed output (imagine the LFO graph as a fat
horizontal line, with the value of the left-most point of the LFOTool graph)
and slowly (based on the rise time) becoming the shape of the visible graph.
This knob is useful for having the LFO slowly influence your sound.

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Control Description

DELAY The amount of time before the rise begins. The LFO has a fixed output, as
described above. After the delay time period, the rise begins.
SMOOTH Smooth the LFO output. This is useful for avoiding abrupt jumps in the LFO
output, without having to draw ramps on every segment of the LFO graph.
PHASE Sets the start position of the LFO phase.
Right-click the PHASE knob and choose Snap to Grid in the context menu
to have the phase value snap to the vertical grid lines (as defined by the grid
parameter at the bottom right of the LFO display).

Unlike Serum 1, the HOST switch now has an effect when BPM is disabled.

With BPM disabled, the HOST switch determines whether phase is calculated from the
host transport sample position on retriggering an LFO. One reason to enable the HOST
switch is to ensure that, even though an LFO is set to FREE, it plays back exactly the same
every time a song is played through.

Conversely, a reason to disable the HOST switch is to allow a truly free-running LFO. Each
time playback of a song starts from the beginning, the LFO phase will continue as if it had
been free-running since the last time playback started.

Using the LFO Editor

Click the button to access a dedicated LFO Editor featuring a larger canvas.

LFO Editor

You can use the same range of tools in the LFO Editor, with the advantage of being able to make finer
adjustments using the larger canvas.

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Assigning an LFO to a Control

You can assign an LFO to a control (knob), causing the LFO to modulate the control. For instance, to
assign LFO 2 to the DETUNE knob in OSC C, click and drag from the LFO 2 tab to the DETUNE knob
in the OSC C panel.

As you are dragging, notice that an LFO 2 label hovers next to the mouse pointer The pointer adds a +
sign as you hover over an assignable knob (in this case, the DETUNE knob).

Assigning LFO 2 to DETUNE

The + sign indicates that you are over a valid mod destination.

When you release the mouse button, Serum

automatically makes the connection causing LFO 2
to now affect the OSC C detune.

After setting this modulation, notice that a number

1 now appears next to LFO 2.

This indicates that LFO 2 has one destination.

Mod Source with One Destination Assigned

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Hover the mouse pointer over the mod source to

display a tooltip showing the destinations.

In this case, LFO 2 displays C Unison Detune as the

assigned destination.

Hovering to Show Destinations

Right-click an LFO tab

to bypass and remove
destinations assigned to the
LFO.

Bypass and Remove Assignments

Setting the Modulator Depth

When you connect a modulation source with a destination,
such as LFO 2 with OSC C DETUNE, a blue halo appears
around the knob (in this case, the DETUNE knob).

This indicates the LFO 2 depth on the DETUNE knob,

defining how much influence the LFO has over the control
DETUNE Modulator Depth at 100%
(knob) position.

A smaller blue halo appears to the top left of the knob. Hovering over this small halo displays an Up/
Down arrow control.

Click and drag the arrow control to change the modulation

depth amount.

As you drag the arrow, notice how the halo shrinks or Setting Modulator Depth
expands to show the range of modulation.

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Alternatively, as a shortcut, you can also Option/Alt-click and drag on the main knob (the
DETUNE knob itself, for example) to change the modulation depth.

Similar to the smaller blue halo, a gray halo appears to the top left of controls that also have a modulator
assigned, but when the modulator source is not currently selected.

To adjust the modulator depth in this case, simply click the corresponding mod source tab and adjust
the depth using the halo.

Alternatively, you can also adjust the depth using the Modulation
Matrix. See “Using the Modulation Matrix” on page 209 for
complete details.

When creating modulations by dragging-and-dropping, the default

type assigned depends on whether the control is centered. For Modulator Deselected
instance, if you drag to a DETUNE knob, which is centered, Serum
assumes you want the mod source to pan both left and right so bidirectional is chosen.

If you drag to a control that is not centered, such as the filter resonance (the RES knob), Serum assumes
you want the modulation to add value only, and unidirectional is used.

You can change the type setting without visiting the modulation matrix window by Shift-
Option-clicking (macOS) or Shift-Alt-clicking (Windows) on the knob with a visible (blue/
yellow) modulation assignment.

Setting Negative Modulation Depths

As described in the previous section, a blue halo around a control indicates the modulation depth of
the corresponding mod source. The blue color indicates a positive value. You can also set the depth to a
negative value using the same Click-drag operation.

When the value becomes negative, the color of the halo changes to a lighter blue. This indicates that
the depth amount is inverted (as the LFO output goes up, the influence on the control goes down).

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Copying a Wavetable Shape to an LFO

You can copy the current wavetable shape from any of the main oscillators (OSC A, OSC B, OSC C) to
an LFO, making it quick and easy to define complex LFO shapes.

To do so, load the appropriate wavetable in the oscillator and use the corresponding WT POS knob to
select the appropriate frame.

Copying a Wavetable to an LFO

Next, select the LFO tab to which you want to copy the wavetable shape, and click the Default menu.

Choose Wavetable A to LFO to copy the currently-selected frame in OSC A to the LFO. The same
applies for oscillators B and C.

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Copying an LFO Shape to a Wavetable

You can similarly copy the current
LFO shape to an oscillator.

Choose or draw the appropriate

shape in an LFO and then
Option-drag (macOS)/Alt-drag
(Windows) the corresponding LFO
tab to the wavetable display for
either OSC A, OSC B, or OSC C.

Copying an LFO Shape to a Wavetable

Modulating LFO Points

You can modulate one or more LFO points (or curves) on an LFO graph, allowing you to create dynamic
or evolving modulations.

LFO point modulation works using LFO busses. Busing allows multiple point modulation by a single
source without requiring you to define duplicate assignments.

You can assign modulation to an LFO point using:

• Bus menus

• Drag and drop

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Modulating LFO Points Using Menus

You can quickly define LFO point modulation using LFO bus menus.

In the LFO display, right-click (Ctrl-click on macOS) a point and choose Modulate X or Modulate Y in
the menu that appears.

LFO Point Bus Menu

Select an LFO bus (initially only LFO Bus 1 appears) and choose a modulation source. The modulation
source you choose will control the LFO point movement. The LFO graph updates to show a shaded bar
representing the modulation range (from minimum to maximum).

You can optionally drag to select multiple points in the LFO graph and configure modulation
for these points in a single assignment.

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Modulating LFO Points Using Drag and Drop

You can also specify a modulation source by dragging the source, such as ENV 2, over an LFO point and
dropping on the X or Y button that appears.

Modulating by Dragging a Source

This allows you to modulate the point either horizontally (X) or vertically (Y), adding the source using the
next available LFO bus.

Using Context Menus with Controls

Each control has a context menu that gives you quick access to useful functions. You can access the
context menu by Ctrl-clicking (macOS) or right-clicking (Windows) the control.

The context menu that appears offers the following options:

Menu Option Description

Mod Source Display all possible modulation sources for the control/knob. Use this
(submenu) menu to quickly configure a connection without having to drag from the
modulation source or visiting the Modulation Matrix window.
Aux Source (submenu) Display all possible auxiliary sources for the control/knob.
Edit Custom Curve Open a curve editor to define a custom mapping applied to the mod source.
Bypass Modulator Bypass the current modulation connection (between the currently-selected
modulation source, such as LFO 1, and the control/knob).
After selecting the option, a check mark appears next to the menu item and
the halo around the control/knob turns gray indicating that the modulation
connection is bypassed. You can reverse this by selecting the menu item
again (uncheck the option).
You can also bypass a modulator by right-clicking the source tile (such as
LFO 1) and choosing the corresponding option.

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Menu Option Description

Remove Modulator Remove the connection between the modulation source and the control/
knob.
Remove All Remove all connections to the control/knob from all modulation sources.
Modulators
Reset Control Reset the control/knob to the default value. This is the same as Cmd-clicking
(macOS) or Ctrl-clicking (Windows) the control.
MIDI Learn Activate MIDI learn mode. When enabled, Serum waits for an incoming
MIDI CC value. After Serum receives a MIDI CC value, MIDI learn mode is
deactivated and the CC# is assigned to the control/knob.
The assignment is saved with the preset (patch).
Remove MIDI cc Remove the MIDI CC# assignment, if any.
Lock Parameter When enabled, lock the parameter (or module) setting (preventing a value
change) when loading presets.

Setting Velocity and Notes

You can use the MIDI velocity and note values, customized through a user-defined graph (curve), to
modulate the full range of parameters available in Serum. By mapping these MIDI inputs to specific
modulation targets using a graph, you gain precise control over how velocity and note data affect
various aspects of the sound.

For example, velocity can dynamically influence parameters like volume, filter cutoff, or even the
brightness of the timbre, enabling nuanced expression that responds directly to your playing intensity.

Similarly, you can map note values to parameters such as oscillator pitch, filter resonance, or effects
settings, allowing the sound to evolve based on the pitch being played. With the flexibility to design and
shape the response curve, you can fine-tune how each parameter behaves across the velocity range or
note spectrum.

This approach not only enhances the expressiveness of your sounds but also opens up creative
possibilities for crafting unique, dynamic, and musically responsive presets.

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Serum Velocity and Notes

Velocity Settings
You can use the velocity tab to define the MIDI velocity graph that
you can later use to modulate the range of Serum parameters.

Click to select the VELO tab, if necessary.

Draw the graph using the tools and operations described in the next
section.

Then modulate one or more Serum controls (such as the filter cutoff,
for instance) using the procedure described later in this section.
Velocity Graph
Right-click the VELO tab and enable Legato (Portamento Time) in
the context menu to have portamento applied to the velocity curve
when a note is triggered and another is already held.

Using the same context menu, choose Init Graph to remove all added points and reset the graph to a
straight diagonal line.

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Drawing the Graph

You can modify the velocity graph by manipulating the graph

directly, adding new points and dragging curves as needed using
your mouse.

Begin by ensuring that the VELO tab is selected.

Modified Velocity Graph

The following table describes operations you can perform when editing the graph:

Operation Display Description

Double-click Add a new point to the mask or remove an existing

point.

Drag a point Move a point to a new location.

Drag a curve point Create or modify a curve between points.

Option/Alt drag a Create or modify curves between all points

curve point simultaneously.

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Modulating a Control

You can assign the velocity graph to a control (such as a

knob), causing the graph to modulate the control.

For example, you might choose to have the velocity

graph modulate the filter cutoff (CUTOFF) setting of
FILTER 1.

To do this, click and drag the VELO tab to the CUTOFF

knob in the FILTER 1 panel.

As you are dragging, notice that an VELO label hovers

next to the mouse pointer. The pointer adds a + sign
as you hover over an assignable knob (in this case, the
CUTOFF knob).

The + sign indicates that you are over a valid mod

destination. When you release the mouse button,
Serum automatically makes the connection causing
VELO to now affect the FILTER 1 cutoff setting.

Velocity Modulating Cutoff

Note Settings
You can use the note tab to define the MIDI note graph that you
can later use to modulate Serum parameters.

Click to select the NOTE tab, if necessary.

Draw the graph using the tools and operations described in the
next section.

Then modulate one or more Serum controls (such as the filter

resonance, for instance) using the procedure described later in this
section.
Note Graph
Right-click the NOTE tab and enable Legato (Portamento Time) in the
context menu to have portamento applied to the note curve when a note is triggered and another is
already held.

Using the same context menu, choose Init Graph to remove all added points and reset the graph to a
straight diagonal line.

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Drawing the Graph

You can modify the note graph by manipulating the graph directly,
adding new points and dragging curves as needed using your
mouse.

Begin by ensuring that the NOTE tab is selected. Then use your
mouse to adjust the graph.

Refer to the table in the “Velocity Settings” on page 202 section

for details about the various drawing operations available.

Modified Note Graph

Modulating a Control

Similar to the VELO graph, you can assign the NOTE

graph to a control (such as a knob), causing the graph to
modulate the control. For example, you might choose to
have the note graph modulate the filter resonance (RES)
setting of FILTER 1.

To do this, click and drag the NOTE tab to the RES

knob in the FILTER 1 panel.

As you are dragging, notice that an NOTE label hovers

next to the mouse pointer. The pointer adds a + sign as
you hover over an assignable knob (in this case, the RES
knob).

The + sign indicates that you are over a valid mod

destination. When you release the mouse button,
Serum automatically makes the connection causing
NOTE to now affect the FILTER 1 resonance value. Note Modulating Resonance

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Using Macros
Serum features eight macros that you can use to simplify the control of multiple parameters
simultaneously. Macros provide an efficient way to design, perform, and tweak sounds without having
to manually adjust numerous parameters one by one.

Macros Pane

For example, instead of adjusting filter cutoff, resonance, and pan individually, you can assign these
parameters to a single macro.

Macros are great for experimenting with sound because small changes to a macro setting can result in
complex shifts across multiple sound elements. Macros are also powerful in live performance setups,
where fast and intuitive control is essential.

In addition to being a modulation source, macros can also serve as a destination. This offers
incredible flexibility when setting up modulation.

For example, consider the case where you want a second aux source to modulate a
destination. You could set a macro as an aux source and then modulate it with another entry
in the modulation matrix, using both a main and aux source.

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Assigning a Macro
You can assign a macro to a control by dragging and dropping the macro selector to the appropriate
control. As you are dragging, notice that a label hovers next to the mouse pointer The pointer adds a +
sign as you hover over an assignable knob (in this case, the DETUNE knob).

The + sign indicates that you are over a valid

mod destination.

When you release the mouse button, Serum

automatically makes the connection causing
the macro to now affect the OSC A detune.

Assigning a Macro to a Control

After setting the macro, notice that

a number 1 now appears next to
MACRO 1.

This indicates that MACRO 1 has one

destination.

Macro with One Destination Assigned

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Hover the mouse pointer over the macro to display a small tooltip showing the destinations.

In this case, MACRO 1 displays A Unison Detune as the

assigned destination.

You can repeat this process and assign the same macro to
multiple controls.

You can then manipulate the macro (perhaps assigned to a knob

or slider on a physical controller) as you would a mod wheel.

Note: As with other modulators, you can set the modulator

depth to offer even finer control over the destination. See
“Setting the Modulator Depth” for more information.

To swap macros, drag and drop a macro over another

macro.
Hovering to Show Destinations
For example, if MACRO 1 is assigned to the WT POS
knob and MACRO 2 is assigned to the PAN knob,
dragging and dropping either macro to the other macro
swaps the assignments.

Using Oscillators and Filters as Modulation Sources

You can use the output of any oscillator or filter as a modulation source.

Drag the module label to a

control to create the modulation
assignment.

At this point, the control is

modulated by the output of the
corresponding oscillator or filter.

Using an Oscillator as a Modulator

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Using the Modulation Matrix
Serum features an easy-to-use modulation matrix that shows all configured modulations as a list. This
at-a-glance view allows you to quickly select the routing and amounts for the various modulation
connections.

Note: Serum offers 64 modulation matrix slots in a patch. You can use these slots to modify or scale up
to 64 destination parameters, one per slot, with 49 different modulation sources.

Serum enhances the typical modulation matrix found on many synthesizers by integrating this matrix
with the drag-and-drop style of routing described in “Exploring Sound Modulation”.

Serum Modulation Matrix

Dragging a modulation source to a control/knob causes the routing to automatically appear in the
matrix and vice-versa. This gives you extra flexibility when viewing, configuring, and modifying your
modulation assignments.

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Exploring the Modulation Matrix

Click the MATRIX tab to access the modulation matrix.

Accessing the Modulation Matrix

You can use the modulation matrix to configure the following options:

Option Description

SOURCE The modulation source, such as LFO 1 for example.

Note that certain modulation sources are only available to set using the
modulation matrix (it’s not possible to drag the source to the control). These
mod sources include:

• Active Voices, derived by dividing the number of active voices by the

maximum number of voices allowed by the POLY count setting.
• Note-On Alt. 1/2, which switches between 0 and 1 at each note-on.
The state of Note-On Alt 2 is the inverse of Note-On Alt 1.
• Note-On Rand (Discrete). The Note-On Rand 1/2 sources send the
same value to each assigned destination at note-on. Destinations
assigned to Note-On Rand (Discrete) each get a different value at
note-on.
• Note-on Rand 1 and 2, which are two separate random numbers
generated on a note on event, in case you need two different random
values for each note on event.
• Oscillators, allowing you to use the output of any oscillator (including
NOISE and SUB) as a mod source.
• Release Velocity
• Voice Index, updated at note-on with a value derived from the current
index of the Voice panel divided by the number of active steps.
• Voice Mod 1/2, updated at note-on with the value of the current step
in the Voice panel for Mod 1/2.
• Expression/MPE X/Y/Z, which are Note Expression or MIDI Polyphonic
Expression (MPE) axes.
• Filters, allowing you to use the output of either filter as a mod source.

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Option Description

SOURCE (cont.) • Mod Wheel

• Aftertouch (channel pressure)
• Poly Aftertouch
• Pitch Bend
• Fixed (not really a modulation source, but you can use this to allow a
modulation assignment to get a fixed value with slider depth control,
should you want that for some reason).
CRV (Curve) Scale the mod source to respond in a non-linear fashion. A 50% value
indicates a linear setting. When the curve is gray, it is bypassed.
Double-click the curve (or right-click and choose Editable Curve in the
menu) to display a curve editor that you can use to define the remapping
curve. Draw the appropriate curve, and use the RISE and FALL smoothing
controls to act as a slew limiter on the source.
AMOUNT The modulation depth, set using a bi-directional slider. Moving the slider to
the left sets a negative value, causing the mod source output to be inverted
before heading to its destination.
Cmd-clicking (macOS) or Ctrl-clicking (Windows) resets the value to the
(zero) default.
Specify whether the modulation is unidirectional or bi-directional.
POL (Polarity) You can achieve similar sonic results with either, it depends on whether you
prefer the destination control (the knob position) to be at the beginning
(unidirectional) or the middle (bi-directional).
DESTINATION The modulation destination. Use the pop-up menu to select the destination
(the parameter modified by the mod source).
OUT A graph that shows the shape of the modulation output.
AUX SOURCE A secondary source to determine the amount of modulation. Use the pop-up
menu to select the aux source.
INV Invert the auxiliary source signal.
Normally, the two modulation sources are “multiplied” together so that one
is scaling the other.
For instance, if LFO 1 is the SOURCE, and ModWheel is the auxiliary source
(AUX SOURCE), the LFO 1 influence is inaudible unless the ModWheel is
raised above zero. This is the default setting.
When set to inverse, the setting is the same as above except that the
secondary source (AUX SOURCE) is value-inverted.
For instance, in the above example, there would be no modulation if the
ModWheel is at maximum, and there would be full modulation if the
ModWheel is at minimum.

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Option Description

CRV (Curve) Scale the auxiliary source to behave in a non-linear fashion. A setting of 50%
designated linear. The curve is bypassed when it is gray.
OUTPUT Scale the final modulation output, allowing for fine tuning.
Select to bypass this row of the modulation matrix (causing it now to have
no effect).

The button changes to show that it is enabled.

Click to remove this row of the modulation matrix. This removes the
modulation assignment from the patch.

Click the button (near the top left) to expand the matrix to show more rows. Alternatively, press
Option-F (macOS)/Alt-F (Windows) to expand the view.

Modulation Matrix (Expanded)

Similarly, click the button to revert the modulation matrix down to the default size. Similarly, press
Option-F (macOS)/Alt-F (Windows) to revert the view to the original size.

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Moving Modulations in the Matrix

To move a modulation row to another location, click and drag the modulation handle to another
location.

Moving a Modulation

Bypassing a Modulation
Every row features a bypass button that allows you to easily bypass the modulation.

Clicking the button bypasses the modulation in the signal routing, indicated by the button updating
to show that the row is being bypassed.

Removing a Modulation
You can remove a modulation assignment directly from the modulation matrix. To do so, click the
button for the corresponding modulation.

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Performing Matrix Operations

You can perform a range of additional operations on the modulation matrix including sorting the matrix,
locking the modulations (even when you change presets), and creating specialized new modulation
assignments.

Click the button (near the top right) and choose an option in the menu that appears.

Modulation Matrix Menu

The following table describes the operations you can perform:

Operation Description

Sort by Source Sort the modulation matrix (ascending) by the SOURCE column.
Sort by Destination Sort the modulation matrix (ascending) by the DESTINATION column.
Lock Matrix (Keep Lock the modulation matrix, which keeps the modulation assignments when
Assignments on you change presets or initialize a new preset.
Preset Change)
Create Vibrato Create a new modulation that maps the next available LFO to “Main Tuning”
(Unused LFO->Pitch using the Mod Wheel.
via Wheel)
Create Velo->Amp Create a new modulation that maps VELO to the Amp.
Assignment
Apply and Delete “Bake” the macro adjustments into the current preset.
Macros
Specifically, for any parameter assigned to a macro, update the current value
of the parameter to include any offset from the macro. Then remove all
modulation assignments for all macros from the modulation matrix.

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Setting Voicing and Portamento
Voicing is the simultaneous vertical placement of notes in relation to each other. Portamento is a pitch
sliding from one note to another.

Serum Voicing and Portamento

Voicing Settings
The VOICING section contains controls that allow you to
change how Serum behaves when multiple notes play at
once.

Serum Voicing Controls

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Mono
Use the MONO switch to enable monophonic mode, causing Serum to only allow one active note at a
time. If a new note is pressed while a note is already playing, the earlier note is interrupted (technically
the note is re-pitched to the new pitch).

Legato
LEGATO is only audible when MONO is enabled. When a monophonic voice is interrupted, the state of
the LEGATO switch determines whether the envelopes/LFOs retrigger.

When LEGATO is enabled with MONO off, Serum behaves paraphonically (especially
noticeable when ENV 2 is modulating a filter). This means you can control envelope
retriggering modes for the effects assignments here also.

When LEGATO is enabled, the envelopes do not retrigger, which results in a smooth change to the new
note. However, sometimes you want the envelopes to retrigger so each note has the same definition; in
these cases, set LEGATO to off.

Note that you can set individual envelopes to behave opposite to the LEGATO setting. See “Inverting
the Legato Setting” on page 185 for more information.

Poly
Use the POLY (polyphony) setting to specify the number of simultaneous notes that can be played.
Sometimes, often for CPU reasons, you might want to place a limit on the simultaneous notes.

For instance if you are sending a flurry of notes (arpeggio) to a patch that has a long release (say 10
seconds), this could end up producing a large number of voices, potentially overloading your CPU.

Typically, eight voices is enough and 16 is generally considered a lot. Note that this control is disabled
when MONO is enabled.

Polyphony Count

This shows the number of voices playing against the total number of voices allowed. In the example,
“0 / 1” indicates that 0 out of a total possible number of 1 voices is playing.

If a note is played, the display would change to “1 / 1”. Similarly, if you enable a second oscillator, the
display would show “0 / 2” when no notes are playing. In other words, Serum totals the number of
voices you have active in a patch.

Single note voice count in Serum includes unison voices and, if one or more oscillators are
set to GRANULAR mode, grain count as well.

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Limiting Polyphony

You can choose to limit same note polyphony. This means that if a note (for example, note number 60)
is already sounding, pressing the same note again won’t trigger another layer of the same note. This
prevents “stacking” multiple instances of the same note, ensuring clarity in the sound and avoiding
unintended overlaps or muddiness.

Right-click the POLY field and choose Limit

Same Note Poly to 1 in the context menu.

This type of polyphony control is useful for

instruments or patches that need to remain
clean, such as bass lines, monophonic synths,
or drum kits where a single sound per note is
preferred.

Serum Voicing Controls

Voice Steal Priority

In cases when the number of voices exceeds the polyphony setting, you can specify which active note
should be terminated when a new note is triggered.

Right-click the POLY field and use the the Voice Steal Priority submenu to choose which voices get
priority (are not stolen) when Serum performs voice stealing, from among the following:

Option Description
Newest Terminate the earliest played note.
Oldest Terminate the most recently played note.
Highest Terminate the lowest-pitched note.
Lowest Terminate the highest-pitched note.
Velocity Note with the lowest input velocity.

Portamento Settings
Portamento creates a slow glide/pitch bend from one note
to another. It is most commonly used (and is most useful)
when MONO is also enabled.

In this case, when one note plays and then another, the
pitch slowly changes from the first note to the second.

Serum Portamento Controls

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Porta
Use the PORTA knob to control the rate of glide from one note to another.

Curve
Use the portamento CURVE to adjust the contour of glide from one note to another. If set convex
(typical use), the note pitch departs the beginning pitch quickly and slows down as it nears the
destination note frequency.

If set concave (dragged down below half), the opposite is true. In this case, the pitch slowly departs the
source pitch and later rapidly arrives at the destination pitch.

Always
When ALWAYS is activated, the portamento occurs on a new note even if no note is currently playing.
When disabled, a note must be held for portamento to occur on the (second) note.

Scaled
The SCALED switch is potentially useful for melodic leads when you want a less noticeable portamento
on short intervals.

When activated, the portamento rate is adjusted based on the distance between the source and
destination pitches. For example, if the portamento is a glide between two notes one octave apart, the
PORTA knob time value is used.

If the portamento is a glide between notes less than one octave apart, the time is faster and vice-versa
(notes larger than an octave are progressively slower).

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Using Clips
Serum features a versatile and fun-to-use CLIP module that you can use to create, fine tune, and play a
series of MIDI clips, directly within Serum.

A MIDI clip contains notes and controller data for playing your current Serum patch. Each clip specifies
the note pitch, length, position, and dynamics (velocity).

Click the button to access the CLIP module.

Serum Clip Mode

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Exploring the CLIP Module

The CLIP module includes several panes to help you navigate and access the various features.

Clips Interface

Use the GLOBAL pane to load a clip bank preset. Alternatively, if you already have clip slots already
populated, you can initialize the CLIP module to start over.

Select a clip slot from among the 12 available.

Use the CLIP SETTINGS pane to set clip parameters, including the clip length, transposition, mode,
rate, launch quantization, and more.

Optionally set the key and scale to have Serum quantize the pitch of notes generated by the CLIP or
ARP module, or from MIDI input..

Populate the piano roll with appropriate notes. You can “click in” the notes or record a live
performance.

Optionally, assign macros to a certain clip settings, allowing you to change one or more sound
parameters using a single knob.

Specify whether Serum should output the MIDI data it generates internally.

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Setting Global Parameters

You can use the GLOBAL pane to set parameters
that affect the general operation of the CLIP
module.

For example, you can use the GLOBAL pane to

load a preset bank, set the trigger mode, and
configure whether parameter edits apply to all
clips.
Global Clip Settings

To load a factory-supplied or user-defined bank,

click the BANK field and choose a bank using the
menu that appears.

The bank loads and populates the clips and

associated settings.

Bank Menu

Use the TRIGGER MODE switch to set the CLIP mode to MONO or POLY. When
set to MONO, only a single clip can play at one time. When set to POLY, you can trigger multiple clips
to play simultaneously.

Enable the EDIT ALL switch to have your parameter edits apply to all clips. When disabled, any
changes to the clip settings (such as TRANSPOSE or RATE) apply only to the currently-selected clip.

When enabled, changes to any parameter become immediately effective for all clips.

Hold the Option (macOS) or Alt (Windows) key when editing a clip parameter to apply the
change to all clips.

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Bank Loaded

Creating a New Clip Bank

In addition to exploring some of the factory-supplied clip banks, you can initialize the clip bank to create
your own from scratch.

Note: Initializing the clip bank

only affects clip bank settings.
This does not change any
of the other sound design
settings you’ve configured
(including oscillators, filters,
arpeggiators, and so on).

Click the BANK menu and

choose Init in the menu.

This initializes the CLIP

module to the default
settings and sets the stage
for you to create a custom
clip bank.
Creating a New Clip Bank

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Saving Clip Banks

After creating a new clip bank, or editing an
existing bank, you can save the entire clip
configuration as a new bank.

Note that clip bank presets that have been

modified display as asterisk (*) after the name.

Clip Bank Modified

Click the BANK field and choose Save Clip Bank in the menu that appears.

A dialog appears allowing you to type the clip bank name.

By default, the clip bank

is saved in a standard
location so that Serum
can easily find it later.

Note that if you try to

save a modified clip
bank that has already
been saved, a dialog
appears allowing you
to give your recently-
modified clip bank a
new name.

This allows you to

freely experiment with Save Clip Bank
changes, saving your
work in steps as you progress.

If you would instead prefer to overwrite the existing clip bank, you can choose the existing file name in
the dialog.

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Working with the Piano Roll

The CLIP module offers a familiar piano roll that you can use to create MIDI clips. You can use the piano
roll to create sequences to go with your sound presets, capturing context along with your sound design,
and offering inspiration to others who might use your preset.

Piano Roll

Begin by selecting a clip from among the 12 available clip slots.

Clip Slots

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Double-click to add a new note. The latest note you added appears in orange.

Adding Notes to the Piano Roll

Click and drag across the piano roll to select notes.

Hold the Shift key while dragging

to select additional notes.

You can also select multiple notes

by Shift-clicking one note after the
other.

Click and drag across the piano

roll without including any notes to
select a time range.

You can then copy/cut and paste

the time range. Notes that overlap
the edge of the time range are Selecting Notes
split.

Important: When pasting a time range, unlike pasting notes, all existing notes in the destination range
are overwritten.

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Click and drag a note to move it to

another location.

When multiple notes are selected,

moving any note moves all
selected notes.

You can also move and adjust

selected notes using the arrow
keys on your keyboard.

Moving a Note

Arrow Description

↑ Move the selected note or notes up one semitone.

↓ Move the selected note or notes down one semitone.
← Move the selected note or notes one position to the right in the grid.
→ Move the selected note or notes one position to the left in the grid.
Shift ↑ Move the selected note or notes up one octave.
Shift ↓ Move the selected note or notes down one octave.
Shift ← Shorten the selected note or notes.
Shift → Lengthen the selected note or notes.

You can perform a series of other operations on notes, as described in the following table. In all cases,
select the appropriate notes and right-click to choose the operation. In addition, in most cases, there’s a
keyboard shortcut to go with the operation.

Action Keyboard Shortcut Description

Cut Cmd-X/Ctrl-X Cut the selected notes.

Copy Cmd-C/Ctrl-C Copy the selected notes.
Paste Cmd-V/Ctrl-V Paste the selected notes at the timeline.
Duplicate Cmd-D/Ctrl-D Duplicate the selected notes at the timeline.
The timeline is set at the end of your selection. So, in
practical terms, end your selection where you would like the
duplicate notes to start.
Delete Backspace Delete the selected notes.
Chop Cmd-U/Ctrl-U Chop the selected notes.

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Action Keyboard Shortcut Description

Conform to Cmd-K/Ctrl-K Move the selected notes to the selected scale (if necessary).
Scale You can select the scale in the Keyboard pane.
Legato Cmd-L/Ctrl-L Apply legato to the selected notes, extending each note to
smoothly connect to the start of the next.
Mute 0 (zero) Mute the selected notes. The muted notes appear in gray.
Quantize Cmd-Q/Ctrl-Q Quantize the selected notes to the current grid setting.
Reverse Cmd-R/Ctrl-R Reverse the order of selected notes.
Scale Time / Halve the time and duration of the selected notes without
50% changing the clip length.
Scale Time * Double the time and duration of the selected notes without
200% changing the clip length.
Double Entire Cmd-E/Ctrl-E Append a duplicate of the clip, copying the notes and
clip doubling the clip length.
Scale Entire (no keyboard Halve the clip length and halve each note’s duration.
clip 50% shortcut)
For example, if the clip is currently two bars long with 8th
notes, this decreases the clip to one bar and halves the note
durations to 16th notes.
Scale Entire (no keyboard Double the clip length and double each note’s duration.
clip 200% shortcut)
For example, if the clip is currently one bar long with 16th
notes, this increases the clip to two bars and doubles the
note durations to 8th notes.
Select All Cmd-A/Ctrl-A Select all notes in the clip.

To delete a single note, double-click on the note. To delete multiple notes, select the notes and press
the Delete key (macOS) or Backspace key (Windows).

Normally, when you select a note, no sound is played. You can have the note sound when selected by
toggling the headphones on. The button changes to show that sound is enabled.

Note that key commands on the piano roll only work if the note grid or automation lane has keyboard
focus. You can give either focus by clicking on the corresponding background.

A keyboard icon appears near the top right to show which pane has keyboard focus.

The Keyboard shortcuts preference needs to be set to ON in the GLOBAL pane to enable key
commands to work.

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Setting the Grid Size

By default, Serum uses a grid size of 1/16 notes in the piano roll. You can change this by clicking the
grid size button and dragging up or down to choose a new setting.

The grid updates as you drag the control. This gives you incredible creative flexibility in terms of rhythm
and precision. A smaller grid size allows for more precise note placement, which is useful when fine-
tuning timing or adding nuanced variations.

For example, you could use a larger grid size (such as quarter notes and eighth notes) to create standard
rhythms like 4/4 beats or simple melodic lines. Smaller grid sizes (such as 16th notes, 32nd notes, or
even smaller) enable more detailed rhythmic work, such as rapid hi-hat patterns, rolls, or syncopated
melodies.

Right-click the grid size button and choose an

option to quickly adjust the grid.

Alternatively, use the corresponding keyboard

shortcut.

Grid Menu

Zooming the Piano Roll

After adding notes to
the piano roll, you can
zoom the piano roll
display to allow you to
focus on the specific
notes.

For example, suppose

that you added the
following notes.

Piano Roll (default zoom)

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Clicking the button

zooms the display,
allowing you to focus on
the notes you entered.

Piano Roll Zoomed

In addition, you can do the following:

• Hold Cmd-Option (macOS) or Ctrl-Alt (Windows) and drag the piano roll background to scroll in
any direction.

• Hold Shift-Option or Shift-Alt and drag the piano roll background to zoom in any direction.

• Hold Shift-Cmd or Shift-Ctrl and drag on the note grid to drag a (black) marquee. The grid zooms
to the selected area after releasing the mouse button.

• Use the mouse wheel to scroll the piano roll vertically or, with Shift held, horizontally.

• Hold the Option or Alt key and use the mouse wheel to zoom the piano roll vertically. Hold the
Cmd or Ctrl key with the mouse wheel to zoom horizontally.

You can also use the mouse wheel while hovering over the timeline (near the top) to zoom
horizontally.

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Folding the Piano Roll

By default, the piano roll displays all notes in the chromatic scale, giving you the flexibility to add any
note to the clip.

Piano Roll with Notes Added

You can “fold” the notes on the piano roll to hide unused notes, making the piano roll appear cleaner
and less cluttered.

Click the button to fold the

piano roll to show only the notes that
you are currently using.

The button highlights to indicate

that the piano roll is folded.

Piano Roll Folded

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The fold feature becomes especially useful when a key and scale are selected. In this case, the piano roll
collapses to display only the notes within the scale.

Hold the Cmd (macOS) or Ctrl (Windows) key when clicking the button to show notes
in the scale as well as used notes.

This makes it easy to distinguish in-scale notes (blue background) from out-of-scale notes (gray
background).

For example, the following shows notes in the C Major scale when the C Minor scale is selected and the
piano roll is folded.

Piano Roll Folded (in relation to the selected scale)

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Managing the Clip Length

To change the clip length in the piano roll, drag the right flag to the appropriate location.

Changing the Clip Length

Similarly, to change the start of the clip,

drag the left flag to the appropriate
location.

To set the start offset marker, click and

drag the marker from the left. The
marker determines where playback
starts when the clip is triggered.

Right-click the marker to display the

context menu.

Clip Marker Menu

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The following table describes the available options:

Option Description

Wrap Clip to Reset the start offset marker to the same position as the start marker
Begin Here moving all notes and automation with it.
Any events that came before the start offset marker are wrapped around to
the end of the clip.
Quantize Quantize the position of the start offset marker when modulation is applied
to the marker.
Also, determine the time division by which each successive key will offset
the playback start position when KB Span is set to Offset (see Configuring
Clip Settings).

Configuring Clip Settings

In addition to adding notes to the piano roll and defining note
properties (such as velocity and expression), you can also configure
a variety of parameters associated with a clip.

Use the CLIP field to load, save, or rename a clip.

CLIP Field

Clip Settings

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The following table describes the remaining parameters you can set:

Field Description

LENGTH The clip length in bars, beats, and 16th notes.

KB SPAN Specifies whether the clip is triggered by MIDI notes, from among the
following options:

• Mono and Poly — Play the clip transposed according to the played note
(relative to C3).
• Offset — Play the clip starting from a different position for each note,
determined by the offset quantize setting (accessed by right-clicking
the start offset marker).
• Off — Turn the setting off.
TRANS The transpose amount for the clip.
MODE The play mode for the clip, specifying how the playhead moves. Note the
following about the available options:

• Random — Playback position jumps between slices at random,

• Rand.No Dup — As above, but never play the same slice twice in a row.
• Rand.Start — The playback position jumps back to a slice each time the
playhead reaches the end of the clip.
• Rand.End — The clip plays for a random number of slices before
jumping back to the start,
• Static — When the clip is triggered, only events at the start position are
sent and the playhead does not move. You can use this to set each clip
to trigger a different chord or a different set of macro values, for
example.
Note: For the random settings, you can also set the associated time, which
divides the clip into “slices” of the selected length.
RATE The speed at which the clip plays.
LAUNCH QUANT The interval at which a triggered clip syncs to the clock/DAW.
RETRIG Specifies whether a clip restarts when triggered, or if the playhead
immediately syncs to the clock/DAW.
VELO TRIG Specifies whether note velocities in a triggered clip are scaled by the
incoming note velocity.
NOTE GATE Specifies whether a “note off” message stops playing a clip when triggered
by input MIDI notes.

Note: If you enabled the EDIT ALL switch in the GLOBAL pane, any changes you make to the
clip settings apply to all clips. When disabled, any changes to the clip settings apply only to the
currently-selected clip.

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Managing Clips
Serum features 12 clips per clip bank. As you’ll see in the next section, this makes it particularly easy
and convenient to trigger these clips using either a MIDI keyboard or even your computer keyboard.

Clip Slots

Click a clip to select it. The current clip is highlighted, and the contents of the clip appear in the piano
roll.

To perform operations on the clip, right-click the clip and

choose an option in the menu that appears.

The following table describes the available operations: Current Clip (Highlighted)

Operation Description

Rename Clip By default, clips are named 1 to 12 (from left to right). You can rename any
clip to better match the clip contents.
After choosing Rename Clip in the menu, a text area appears in the clip
header.
Type the new clip name and press the Enter key.
Copy Clip Copy the clip contents (notes) and settings (including the clip name) to
Serum’s internal clipboard.
Right-click the source clip and choose Copy Clip in the menu. Right-click the
destination clip and choose Paste Clip in the menu.
Note that it is not possible to copy a clip from one instance of Serum to
another.
Paste Clip Paste the most-recently copied clip into the target clip.
Erase Clip Erase the contents of the selected clip.
Set as Preview Clip Set the clip as the MIDI sequence to play when someone previews the
saved preset in the Serum presets browser.

When designing sounds, both for yourself and others, it’s helpful to set a preview clip. This
gives preset users a quick sense of the intent of the preset. Otherwise, Serum plays a
designated “fallback” clip, which can quickly get repetitive when previewing a lot of presets.

Plus, by including one or more clips with your preset, you offer yourself and others a bonus
when you choose to use the sound in the future!

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Triggering Clips
You can trigger your clips in multiple ways, allowing clips to be a versatile part of your sound design
process.

To trigger a clip while in CLIP mode, click the

button for the corresponding slot.

The clip starts playing and the button changes to a stop

button to indicate which clip is currently playing.

To stop a clip, click the button (for the

corresponding clip). Clip Slot with Play Button

You can make changes to any aspect of the clip while it is playing, including modifying notes, changing
clip settings, and more. You can also change the underlying sound design as the clip plays, providing a
versatile way to hear your sound evolve in context.

You can also trigger clips using the CLIP keyboard.

This is helpful when you are not in CLIP mode and instead
tweaking the oscillators, mixing, applying effects, or adjusting
the modulation matrix.

Notice that the clip slots (in CLIP mode) are arranged similar to Clip Keyboard
a keyboard. This makes it easy to logically map the clips slots
to the CLIP keyboard.

Press a key to (continuously) play the corresponding clip. The

key highlights in green.

Notice a small green indicator in the lower right corner. This

flashes in rhythm with the notes played when you launch a Clip Keyboard (Playing)
clip.

If you launch a clip without notes, the key highlights in green but the rhythm indicator is not present.

Press the same key to stop the clip, or press another key to launch the corresponding clip.

Important: If you launch a clip that you know has notes but don’t hear any sound, verify that clip
playback is enabled.

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Recording Your Clips

In addition to “clicking in” notes using a mouse,
you can also create clips by recording a
performance using a MIDI controller.

Begin by choosing a destination clip slot and

then select either OVERDUB or EXTEND as the
recording mode. Recording Clips

OVERDUB loops continuously using the start and end markers that you set, allowing you to add new
notes during each pass. EXTEND, in contrast, extends the piano roll timeline until you either stop
recording or switch to OVERDUB mode. You can change between the two modes at any time.

You can activate or deactivate the metronome as needed. Click the

button to start recording.

The RECORD pane changes to offer you additional

controls to manage the recording process.

Play the appropriate notes using a MIDI controller.

The notes you play appear in red.

Recording In Progress

Recorded Notes Appear in Red

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Click the button to commit your most recent performance to the clip. The notes change from red
to green to indicate the committed status.

Committed Notes (in green)

After committing, any new notes that you play appear in red (while the committed notes remain green).

Click the button to undo your last performance (notes not committed to the clip).

When you’ve finished, click the button. All notes become “committed” and appear in green.
Note, however, that the clip continues to play.

To stop playback, click the stop button for the corresponding clip.

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Managing MIDI Out

You can specify how Serum should output MIDI
data.

Right-click the MIDI OUT field to choose an

option using the menu. You can choose from
among the following:

• Off — The default. Do not output MIDI data

to the host.

• Clip Player — Output MIDI data from only

the CLIP module, with no key/scale pitch
quantizing applied.
MIDI Out Menu
• On — Output MIDI data from the CLIP
module, through the ARP module (if enabled),
with key/scale pitch quantizing applied.

Independent of the setting, the display shows

the generated notes that get routed to the synth
engine in Serum.

MIDI Out Data

Routing MIDI to Another Instrument

With MIDI OUT enabled (set to either On or Clip Player), you can route the MIDI output from Serum
to another instrument (track) in your DAW.

The specific setup to do this depends on your DAW. The following describes how to configure this
using Apple Logic Pro X.

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Begin by creating a New Software

Instrument Track and adding Serum 2 as the
instrument. This track is called Source in this
example.

Then create a second software instrument

track (called Destination) and add any
instrument (in this example, Classic Electric
Piano). Logic Pro X Instrument Tracks

Expand the Track information for the

Destination.

Expanded Track Information

Click the Internal MIDI In field, expand the

Instrument Output menu, and choose the
source (Source - Serum 2 in this example).

The MIDI from the Serum CLIP player and/or

arpeggiator is now routed to the Destination Logic Pro X Instrument Tracks
instrument.

Important: Remember that MIDI OUT in Serum needs to be enabled (set to either On or Clip Player).

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Configuring the Clip Module

You can configure the CLIP module using the
main context menu.

CLIP Menu

The following describes the options:

Operation Description
Lock Module Enable this option to lock the entire CLIPS module, including all loaded clips,
when changing (sound) presets.
MIDI Input Trigger Select the octave from which notes trigger clips. Alternatively, set to Off if no
Octave triggering is required.
By default, this is set to the lowest octave of the MIDI note range.

Using Macros
You can assign macros to a number of controls within the CLIP module, thereby allowing you to change
one or more sound parameters using a single knob.

In addition, you can use any existing macro assignments to tweak the sound without having
to leave CLIP view. Furthermore, you can record macro automation to a clip by dragging the
macro knobs.

Click the button. The macros pane appears.

Macros Pane (in the CLIPS module)

To assign a macro to a control, drag and drop the macro selector to the appropriate control. The +
sign indicates that you are over a valid modulation destination. Note that not all controls are valid
destinations.

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When you release the mouse button, Serum automatically makes the connection causing the macro to
now affect the destination control.

Assigning a Macro to a Control

After setting the macro, notice that a number 1 now appears next to MACRO 1. This indicates that
MACRO 1 has one destination.

Macro with One Destination Assigned

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Hover the mouse pointer over the macro to display a small tooltip showing the destinations.

Hovering to Show Destinations

In this case, MACRO 1 displays Clip 1 Rate as the assigned destination.

You can repeat this process and assign the same macro to multiple controls. You can then manipulate
the macro (perhaps assigned to a knob or slider on a physical controller) as you would a mod wheel.

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Using the Arpeggiator
Serum features a versatile, full-featured arpeggiator designed to effortlessly sequence the notes of a
chord into rhythmic patterns, enabling you to create dynamic, flowing musical phrases with ease.

Serum offers a broad array of patterns, fully customizable through parameters such as transposition,
offsets, repeats, and chance, among others, giving you precise creative freedom.

Using the arpeggiator, you can swiftly craft intricate, evolving musical expressions that transform simple
chords into captivating, complex melodies.

Click the button to access the Serum arpeggiator.

Serum Arpeggiator

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Exploring the Arpeggiator

The ARP module includes several panes to help you navigate and access the various features.

Arpeggiator Module

Use the GLOBAL pane to set parameters that affect all aspects of the arpeggiator, including the launch
quantization and whether parameter edits affect all arp slots. You can also use the GLOBAL pane to
load arpeggiator presets, create a new arp bank, and save your own arp bank as a user-defined preset.

Use the PATTERN pane to set the shape of the currently-selected arp slot (or all arp slots if you
selected that EDIT ALL option in the GLOBAL pane). You can also use this pane to set the arpeggiator
rate (in either beats per minute or Hertz), and enable triplets and dotted notes.

Use the TRANSPOSE pane to set the transpose shift (positive or negative) and range for the
arpeggiator (which specifies how many times the pattern is transposed by the shift setting). You can also
set the shape of the transpose range, which further expands your creative possibilities.

Use the PLAYBACK pane to specify the playback settings for the arpeggiator, including offsets and
repeats, as well as the length of the gate and the probability of a note being played. You can also enable
a latch to continue playing notes without needing to keep the keys pressed down, as well as pass
incoming notes to the output (similar to a MIDI THRU port on a device) .

Use the RETRIGGER pane to specify how the arpeggiator retriggers the arp shape/pattern. You can set
to retrigger the arp when the slot is launched or on a incoming note (first note or otherwise). You can
also specify the rate at which the arpeggiator is retriggered.

Use the VELOCITY pane to configure the arpeggiator to raise or lower the arpeggiator note output
velocities over time. You can set the speed at which the velocities are changed (decay) as well as the
target velocity towards which the decay setting moves.

The ARP module further features 12 arpeggiators per arp bank. This offers a rich playground in which to
explore and define evolving rhythmic patterns and dynamic musical phrases.

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Setting Global Parameters

You can use the GLOBAL pane to set
parameters that affect all aspects of the
arpeggiator.

For example, you can use the GLOBAL

pane to load an arp bank, set the launch
quantization, and configure whether
parameter edits apply to all arp slots.

You can also create a new arp bank and save

Global Arpeggiator Settings
your own arp bank as a user-defined preset.

To load a factory-supplied or user-defined

bank, click the BANK field and choose a bank
using the menu that appears.

The bank loads and populates the arpeggiator

slots and associated settings.

Bank Menu

Set the LAUNCH QUANT by clicking in the

field and dragging up or down.

This specifies the interval at which a triggered

Launch Quant Setting
arp syncs to the clock/DAW.

Enable the EDIT ALL switch to have your parameter edits apply to all arp slots.

When disabled, any changes to the arp settings (such as TRANSPOSE or CHANCE) apply only to the
currently-selected arpeggiator slot.

When enabled, changes to any parameter become immediately effective for all arp slots.

Hold the Option (macOS) or Alt (Windows) key when editing an arp parameter to apply the
change to all arps.

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Creating a New Arp Bank

In addition to exploring the factory-supplied arp banks, you can initialize the bank and create your own
arpeggiator bank.

Note: Initializing the

arpeggiator bank only affects
arp bank settings. This
does not change any of the
other sound design settings
you’ve configured (including
oscillators, filters, clips, and
so on).

Click the BANK menu and

choose Init in the menu.

This initializes the ARP

module to the default
settings and sets the stage
for you to create a custom Creating a New Arp Bank
arpeggiator bank.

Saving Arp Banks

After creating a new arp bank, or editing an
existing bank, you can save the entire arpeggiator
configuration as a new preset.

Note that arp bank presets that have been

modified display as asterisk (*) after the name.

Click the BANK field and choose Save Arp Bank in

the menu that appears.
Arp Bank Modified
A dialog appears allowing you to type the arp bank
name.

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By default, the arp bank is

saved in a standard location
so that Serum can easily find
it later.

Note that if you try to save

a modified arp bank that has
already been saved, a dialog
appears allowing you to give
your recently-modified arp
bank a new name.

This allows you to freely

experiment with changes,
saving your work in
increments as you progress. Saving an Arp Bank

If you would instead prefer to overwrite the existing arp bank, you can choose the existing file name in
the dialog.

Setting the Arp Pattern

You can set the shape of the arp pattern, as well as rate, triplets, and dotted note settings.

In the SHAPE field, click and choose an option using

the menu that appears.

Serum offers a wide range of arpeggiator shapes,

including standard up/down patterns as well as less
familiar shapes such as Converge and Diverge, together
with a collection of random shapes.

To set the arpeggiator rate, begin by selecting either

BPM (beats per minute) or HZ (Hertz). Then click and
drag either the RATE knob or the value field directly to Pattern Settings
the right of the knob (both work identically). To set a
specific value, double-click either the knob or the field and type the appropriate value.

Click the TRIP button to enable triplets. Click the DOT button to enable dotted notes.

Important: The parameters you set in this and the other panes only affect the currently-selected arp
slot unless you enabled EDIT ALL in the GLOBAL pane..

One way to try all the various shapes is to enable the LATCH button (in the PLAYBACK
pane), play a chord on your MIDI controller, and then cycle through all the shapes one by one
to hear the difference. You can also watch the Serum keyboard to get a visual sense of how
the shape arpeggiates the chord.

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Creating a Custom Pattern

You can define a custom arpeggiator using Serum’s
advanced pattern editor.

Choose Pattern in the SHAPE field, and click the

button.

The button highlights and the arp editor appears

in the top half of the interface.

Pattern Option

Use the left panel to specify the pattern settings and the right panel to configure the arpeggiator graph.

Arp Editor

Loading a Pattern
You can quickly load a factory-supplied
or user-defined pattern.

Click the pattern name (topmost) field

and choose a pattern using the menu
that appears.

The pattern loads and populates the arp

graph and associated settings.

Creating an Arp Pattern

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Creating a New Pattern

You can create a new pattern, or reinitialize the pattern editor, at any time.

Note: Initializing the pattern only affects

current arp pattern settings. This does
not change any of the other arp bank
settings.

Click the pattern name field and choose

Init in the menu.

This initializes the pattern editor to

the default settings and provides an
opportunity for you to create a new
pattern.

Creating an Arp Pattern

Configuring the Pattern Settings

You can use the PATTERN SETTINGS pane to specify
parameters that affect the entire arp pattern.

For example, you can use the pane to set the pattern
length, the mode (normal, reverse, and so on), the step
mode, and the wrap settings.

Pattern Option

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The following table describes the parameters you can set:

Field Description

LENGTH The pattern length in bars, beats, and 16th notes.

MODE The mode of the pattern specifying how the playhead moves, from among
the following:

• Normal
• Reverse
• Pendulum
• Random
• Rand Start
• Rand End
• One Shot
• Static
TIME For random play modes, specifies how often the playhead jumps to a new
random position. You can choose from values between 1/16th note and four
bars.
STEP MODE Specifies how each step is played, from among the following:

• Normal
• New Only
• Chord
• Chord (new)
The chord triggers all held notes on each step with voicing determined by
step numbers.
Note that new modes trigger a step only if the input note is received exactly
at the same time as the step triggers.
WRAP Specifies how pattern steps less than, or greater than, the number of held
keys are treated.
PITCH The wrap transpose, from 0 to 24 semitones.
RANGE Specifies how pattern steps less than, or great than, the number of held keys
are transposed.

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Saving a Pattern
After creating a new pattern, or modifying an
existing pattern, you can save the configuration
as a new pattern.

Note that pattern presets that have been

modified display as asterisk (*) after the name.
Pattern Modified

Click the pattern name (topmost) field and choose Save Pattern in the menu that appears.

A dialog appears allowing you to type the arp

pattern name.

By default, the pattern is saved in a standard

location so that Serum can easily find it later.

Note that if you try to save a modified pattern that

has already been saved, a dialog appears allowing
you to give your recently-modified arp pattern a
new name.

This allows you to freely experiment with changes,

saving your work in steps as you progress.
Saving a Pattern
If you would instead prefer to overwrite the existing
arp pattern, you can choose the existing file name in the dialog.

Renaming a Pattern
You can rename a pattern, as needed.

Click the pattern name field and choose Rename

Pattern in the menu that appears.

Type the new name of the pattern.

Renaming a Pattern

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Using the Arp Graph Editor

The pattern editor features an advanced graph editor that you can use to create the arp graph. You can
use the graph editor to interactively create complete patterns in the context of your current patch.

Graph Editor

Click the grid size and drag up or down to change the default grid setting.

Scroll the grid up or down by clicking and

dragging in the Step area. You can also scroll
up or down using the mouse wheel.

Double-click to add a new note event in the

arp graph. The latest note event you added
appears in orange.

The arp graph offers capabilities very similarly

to the piano roll in the CLIP module. For
example, you can click and drag across the
graph to select note events, and copy/cut
and paste events to a new area in the graph.

You can also select and move note events

around the graph. See “Working with
the Piano Roll” on page 224 for more
information.

Double-click in the Accent lane to add an

accent to the corresponding note event.
Double-click in the Strum lane to add
strumming to the corresponding area. Saving a Pattern

Use the automation lanes to control various parameters over time. Right-click in various places in
the arp grid to display a context menu for the corresponding element.

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Transpose Settings
You can set the transpose shift and range for the
arpeggiator.

Click and drag the SHIFT knob to set the amount that
each repetition of the pattern is transposed. This can
be a positive or negative value.

Click and drag the RANGE knob to specify how many

times the pattern is transposed by the SHIFT setting.

To set the shape of the transpose range, right-click Transpose Settings

the RANGE knob and choose an option in the menu
that appears.

Transpose Range Shape Menu

The following table describes the range shape options available. Note that each example uses a SHIFT
setting of 3 and a RANGE setting of 4.

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Shape Description

Up Transpose the arpeggiated notes by the SHIFT setting and repeat the
number of times specified by the RANGE setting.

Down Transpose the arpeggiated notes by the SHIFT setting and repeat the
number of times specified by the RANGE setting.

Up/Down Transpose the arpeggiated notes by the SHIFT setting and repeat the
number of times as specified by the RANGE setting.
Then immediately reverse (transpose the arpeggiated notes in the reverse
direction and repeat using the same settings).

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Shape Description

Down/Up Transpose the arpeggiated notes by the SHIFT setting and repeat the
number of times specified by the RANGE setting.
Then immediately reverse (transpose the arpeggiated notes in the reverse
direction and repeat using the same settings).

Up+Down Transpose the arpeggiated notes by the SHIFT setting and repeat the
number of times specified by the RANGE setting.
Then start again in the reverse direction.

Down+Up Transpose the arpeggiated notes by the SHIFT setting and repeat the
number of times specified by the RANGE setting.
Then start again in the reverse direction.

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Shape Description

Thumb Up Transpose the arpeggiated notes by the SHIFT setting.

After each transposition, play the original arpeggio followed by another
transposition. Repeat the number of times specified by the RANGE setting.

Thumb UD Transpose the arpeggiated notes by the SHIFT setting.

After each transposition, play the original arpeggio followed by another
transposition. Repeat the number of times specified by the RANGE setting.
Then immediately reverse (transpose the arpeggiated notes in the reverse
direction and repeat using the same settings).

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Shape Description

Pinky Up Transpose the arpeggiated notes to the maximum (as specified by the
SHIFT and RANGE settings). After each transposition, play the maximum
transposition followed by the original arpeggio transposed.
Repeat the number of times specified by the RANGE setting.

Pinky UD Transpose the arpeggiated notes to the maximum (as specified by the
SHIFT and RANGE settings). After each transposition, play the maximum
transposition followed by the original arpeggio transposed.
Repeat the number of times specified by the RANGE setting.
Then immediately reverse (transpose the arpeggiated notes in the reverse
direction and repeat using the same settings).

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Shape Description

Converge Transpose the arpeggiated notes to the maximum (as specified by the SHIFT
and RANGE settings). After each transposition, converge the transpositions
between original to maximum.

Diverge Transpose the arpeggiated notes as specified by the SHIFT setting. After
each transposition, diverge the transpositions further.

Con+Diverge Transpose the arpeggiated notes first using the converge pattern followed
by the diverge pattern (see above).

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Shape Description

Chord Use the SHIFT and RANGE settings to play the chord instead of the
arpeggio.

Random Randomly transpose the arpeggiated notes based on the SHIFT setting and
repeating the number of times specified by the RANGE setting.

Rnd.NoDup Randomly transpose the arpeggiated notes (without duplicates) based

on the SHIFT setting and repeating the number of times specified by the
RANGE setting.

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Shape Description

Rnd.Drift Randomly transpose (with a bias towards drifting) the arpeggiated notes
based on the SHIFT setting and repeating the number of times specified by
the RANGE setting.

Rnd.Once Randomly transpose the arpeggiated notes once based on the SHIFT setting
and repeating the number of times specified by the RANGE setting. Then
continue using this pattern.

Playback Settings
You can specify the playback settings for the arpeggiator, including offsets and repeats, as well as the
length of the gate and the probability of a note being played.

Click the LATCH button to continue

playing notes without needing to keep the keys
pressed down. The button highlights when
enabled.

Click the THRU button to pass the

incoming notes to the output (in a conceptually
similar way to a physical MIDI THRU port on a
device).
Playback Settings
When this setting is disabled, the arpeggiator
consumes the input; when enabled, the notes are passed through and played.

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Click and drag the following knobs to perform the associated action:

Knob Description

OFFSET Offset the order of the arpeggiator notes.

REPEATS Set the number of times the pattern and transpose range are repeated.
GATE Set the length of the arpeggiator notes, relative to the RATE setting.
CHANCE Set the probability of a note being played.
Right-click the knob and choose Pre in the menu to apply the CHANCE
setting before the SHAPE pattern is advanced. You can use this to
guarantee that the next note played is always next in the sequence.

When the arp is enabled, MIDI CC64 sustain messages sent to Serum will control the latch
instead of regular note sustain.

Retrigger Settings
You can specify how the arpeggiator retriggers the arp shape/pattern.
Enable the LAUNCH setting to retrigger the arp when the slot is
launched.

Enable the RATE setting and set an appropriate rate by clicking and
dragging the field. The rate sets the interval at which the arpeggiator is
retriggered.

Enable the NOTE setting to retrigger on an incoming note.

Retrigger Settings
Similarly, enable the FIRST setting to retrigger only on a first incoming
note, as would be the case for held notes in a chord.

Velocity Settings
You can set the arpeggiator to raise or lower the arpeggiator note
output velocities over time. Enable the VELOCITY setting to activate
the velocity settings (in this section).

Enable the RETRIG setting to reset the velocity decay value (back to
incoming velocities) whenever the RETRIGGER feature is activated.
(See the previous section for more information about retrigger settings.)

Click and drag the DECAY knob to set the speed at which the velocities
are changed.

Click and drag the TARGET knob to set the target velocity towards which Velocity Settings
the DECAY setting moves.

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Managing Arpeggiators
The ARP module features 12 arpeggiators per arp bank (similar to the CLIPS module). This makes it easy
and convenient to trigger these arps using either a MIDI keyboard or your computer keyboard.

Arpeggiator Slots

Click an arp slot to select it. The current arpeggiator is highlighted and the play button turns purple. The
arp settings appear in the various sections.

To perform operations on the arpeggiator, right-click the arp

and choose an option in the menu that appears.

Current Arp (Highlighted)

The following table describes the available operations:

Operation Description
Rename Pattern By default, arpeggiators are named after the pattern shape, such as Up (1/16)
or Down (1/32).
When you define the pattern yourself (by choosing Pattern in the SHAPE
field and then using the pattern editor), you can rename the arp to better
describe the pattern you created.
Right-click in the arp and choose Rename Pattern in the context menu. A
text area appears in the clip header.
Type the new pattern name and press the Enter key.
Copy Pattern Copy the arp settings to Serum’s internal clipboard.
Right-click the source arp and choose Copy Pattern in the context menu.
Right-click the destination arp and choose Paste Pattern in the menu.
Note that it is not possible to copy a pattern from one instance of Serum to
another.
Paste Pattern Paste the most-recently copied arp into the target arp.
Erase Pattern Erase the contents of the selected arp.
Show Pattern Names Show the arp names in the slots.

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Triggering the Arpeggiator

You can trigger an arpeggiator using the play button or the arpeggiator keyboard.

To trigger an arpeggiator while in ARP mode, click the

button for the corresponding slot.

The arp starts playing and the button changes

to indicate which arp is currently playing.

To stop an arpeggiator, stop the MIDI input to the

arpeggiator either by releasing the keys, stopping a playing Arpeggiator Slot with Play Button
clip, or disabling the latch (if enabled).

You can make changes to any aspect of the arp while it is playing, including changing patterns,
modifying arp settings, and more. You can also change the underlying sound design as the arp plays,
providing a versatile way to hear your sound evolve, in context.

You can also trigger clips using the ARP keyboard.

This is helpful when you are not in ARP mode and instead
tweaking the oscillators, mixing, applying effects, or adjusting
the modulation matrix.

Notice that the arp slots (in ARP mode) are arranged similar Arpeggiator Keyboard
to a keyboard. This makes it easy to logically map the arp
slots to the ARP keyboard. Press a key to play the corresponding arp. The key highlights in purple.

Press the same key to relaunch the arp, or press another key to launch that arp.

Important: If you launch an arp but don’t hear the sequence that you expect, verify that arp playback is
enabled.

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Managing MIDI Out

You can specify whether Serum should output
MIDI data from the CLIP player, the ARP
(arpeggiator), or neither.

By default, MIDI OUT is set to Off, which means

that Serum does not output MIDI data to the host
(DAW).
MIDI Out Pane

Otherwise, the display shows the corresponding

MIDI data stream.

MIDI Out Data

Right-click the MIDI OUT field to choose an

option using the menu. You can choose from
among the following:

• Off — The default. Do not output MIDI data

to the host.

• Clip Player — Output MIDI data from only the

CLIP player.

• On — Output MIDI data from both the CLIP

player and the arpeggiator.

MIDI Out Menu

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Configuring the Arp Module

You can configure the ARP module using the
main context menu.

ARP Menu

The following describes the options:

Operation Description
Lock Module Enable this option to lock the entire ARP module, including all arps, when
changing (sound) presets.
MIDI Input Trigger Select the octave from which notes trigger arps. Alternatively, set to Off if no
Octave triggering is required.
By default, this is set to the lowest octave of the MIDI note range.

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Serum features an on-screen keyboard that you can use to play notes as well as set a range of
parameters that affect MIDI input and output.

Serum Keyboard

Use the TRANSPOSE field to transpose the keyboard within a range of two octaves (set in
semitones).

Use the KEY and SCALE fields to choose appropriate options. Serum offers a very thorough list of
scale options from which to choose.

Use the SWING field to set the swing applied to certain notes to add groove.

And finally, use the OSC MAPPING feature to edit the note ranges of the oscillators and
arpeggiator.

Transpose
You can transpose the keyboard within a range of -24 to +24 semitones.

Keyboard Transpose

Click the TRANSPOSE field and drag up or down. Alternatively, for even finer control, click the up and
down arrows to adjust the setting by a single semitone.

You can also hover over the field and adjust the setting by 12 semitone increments using the mouse
wheel.

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Setting the Key and Scale

You can set the key and scale within Serum. These settings, together with the TRANSPOSE setting
(described above), are applied to both MIDI input and the output of both the CLIP and ARP modules.

Key and Scale

Serum offers a comprehensive selection of scales.

Scale Options

After selecting the key and scale, the piano roll in the CLIP module highlights the root note of the key.
In addition, notes within the scale are highlighted with a gray background, while notes outside the scale
appear with a darker gray background.

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Setting Swing
You can set the swing applied to certain notes to add groove, thereby imparting a more human feel
instead of a rigid, machine-like rhythm.

Swing

Click the SWING field and drag up or down. The range of swing values depends on the host DAW that
you are using (see the note below). You can also hover over the field and adjust the setting using the
mouse wheel.

By default, swing is set to OFF. As soon as you move

away this setting, a second field appears showing the
swing division.

Click and drag to set the appropriate division. You can also use a mouse wheel or the arrow buttons.

Serum attempts to match the swing value displayed to the convention used in the host
DAW. This means that setting the same values in Serum and the host should result in the
same amount of swing.

For example, when using Ableton Live, swing is displayed as a range between 12.5% and
87.5%. In contrast, FL Studio displays swing with a range of -150% to 150%.

Oscillator Mapping
You can edit the note ranges of the oscillators and arpeggiator to define and limit the range of notes to
which the oscillator or arpeggiator responds.

Oscillator Mapping

Click the OSC MAPPING button. The oscillator mapping dialog appears.

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Oscillator Mapping Editor

To set the key mapping, select KEY in the MAPPING

section (lower left).

Click and drag the left or right edge of the note range for
the corresponding oscillator or arpeggiator.
Key Mapping
The current note appears below the cursor, and a highlight
shows the note in the context of the keyboard.

Setting the Note Range

To move a note range, drag the range to the new location.

macOS Note that the “hand” looks

slightly different when
moving a note range on
Windows macOS and Windows.

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The current note boundaries appear below the cursor (hand), and highlights show the note range in the
context of the keyboard.

Moving a Note Range

You can double-click a range to type specific values into the

text box that appears.

Use the same notation that appears on the keyboard below

the ranges.

Use the FOLD checkbox to specify what happens to notes outside the selected range. When
unselected, the notes are ignored. When selected, the notes get “folded” into the selected range. You
can use this, for example, to restrict the range of an oscillator used for sub-bass to a single low octave,
regardless of the octave the incoming note was played.

Select the WARP checkbox to set the corresponding oscillator to warp other oscillators when keys are
played outside of its note range. For example, consider the case when the OSC A warp is set to FM
from B. If you want the warp to apply regardless of the OSC B note ranges, select the WARP checkbox
for OSC B. This allows you to restrict the OSC B note range without losing the warp on OSC A for
notes outside of the OSC B range.

You can define note ranges to do the following:

• Create splits and layers

You can assign different oscillators to specific note ranges to create multi-layered sounds or
keyboard splits. For example, you might create bass and lead layers, assigning one oscillator to low
notes for a bass sound and another to high notes for a lead.

Similarly, you could create complex pads by layering different oscillators with unique timbres across
the keyboard range for rich, evolving textures.

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• Emulate acoustic instruments

Many acoustic instruments have distinct tonal characteristics across their range. Assigning
oscillators to specific note ranges can mimic this behavior.

For example, you could consider simulating how low strings sound warmer while higher strings
sound brighter on a string instrument.

• Add specific harmonic content to note ranges

You could create timbral variation by assigning unique waveforms and effects to different note
ranges. For example, you could consider using a sine wave oscillator in the lower range for pure
bass tones and a saw wave in higher ranges for harmonic richness.

This could thereby enhance expressiveness by varying the oscillator’s contribution based on the
note range.

Mapping Velocity Ranges

You can edit the velocity ranges of the oscillators and arpeggiator to define and limit the range of
velocities that the oscillator or arpeggiator can produce.

Right-click any oscillator header and choose Edit Note

Ranges in the menu. The Mapping Editor appears.

To set the velocity mapping, select VEL in the MAPPING

section (lower left). Velocity Mapping

Velocity Mapping Editor

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Click and drag the left or right edge of the velocity range for the corresponding oscillator or arpeggiator.
The current velocity appears below the cursor, and a highlight shows the velocity in the context of the
complete range (1 to 127).

Setting the Velocity Range

To move a velocity range, drag the range to the new location.

The current velocity boundaries appear below the cursor (hand), and highlights show the velocity range
in the context of the complete range (1 to 127).

Moving a Velocity Range

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Using the Wavetable Editor
Serum features an advanced Wavetable Editor
that makes it fun and easy to create and edit
wavetables.

To access the Wavetable Editor, click the

button in the OSC A, OSC B, or OSC C pane.

The Wavetable Editor appears.

Accessing the Editor

Wavetable Editor

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Using the Thumbnails

Thumbnails appear along the bottom of the Wavetable Editor.

Wavetable Editor Thumbnails

Thumbnail overviews provide an easy way to view, select, and reorder the subtables that make up a
wavetable.

You can use the thumbnails to perform a variety of functions:

Thumbnail Action Description

Click View and edit the specific frame (subtable).

Click-drag Move a frame to a new location. As you drag left or right, a yellow vertical
cursor appears showing where the frame will relocate after you release the
mouse.
Shift-click Select a range of frames. After selecting a range, you can perform operations
such as Remove: Multiselection and Remove All (Except Selected), among
others.

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Using the Drawing Tools

The Wavetable Editor offers a toolbar that you can use to draw in the main display. Each tool operates
in relation to the grid size (set in the lower-right corner of the main waveform).

Wavetable Editor Toolbar and Grid Size

Tool Name Description

Flat Line The default tool. Draw a flat line in the grid step.

Sine Draw a sine wave. This is useful for adding a pure

harmonic at the grid size.
For example, if the grid is set to 4, this tool adds an
overtone two octaves above the fundamental.

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Tool Name Description

Slope Up Draw a diagonal line upwards. This is useful for drawing

small saws to give your waveform a buzz.

Slope Down Draw a diagonal line downwards. This is useful for drawing
small saws to give your waveform a buzz.

Curve up Draw a quarter-sine waveform.

Curve down Draw a quarter-sine waveform.

Half sine (peak) Draw a half-sine waveform.

Half sine (valley) Draw a half-sine waveform.

Interpolate linear Rather than drawing, this tool connects endpoints to draw
a straight line across the grid segment.
This can be useful for smoothing out a waveform (LPF).
Interpolate curved Similar to interpolate linear, however with a more gradual
transition (not as much harmonics as linear; even more
low pass/smoothed).
Nudge Move a portion of the waveform up or down. Use this for
clipping (if you click-drag vertically far enough, the audio
begins to clip/flat-line).
Noise Add noise to the waveform. Dragging vertically up adds
noise, while dragging down reduces noise.

Mirror Create a symmetrical wavetable drawing by mirroring from

the center.

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FFT Area
Use the FFT area to draw the waveform harmonics and their relative phases to one another.

Wavetable Editor FFT Area

The top section shows the frequency bins. The left-most bin represents the fundamental or single sine
wave at the oscillator’s base frequency (the note you play).

The vertical bars to the right represent the harmonics that make up the sound, (2:1 is the octave, 3:1 is
+19 semitones, 4:1 equals 24 semitones, and so on).

The bottom section shows the phase offset for each harmonic. Right-click to display the context menu.

Shift-Cmd-click (macOS) or Shift-Ctrl-click (Windows) in the bottom section to nudge the

phase offset to the right.

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Wavetable Editor FFT Menu

There is a separate menu for the frequency and phase bins.

Menu Item Description

Clear All Zero out all bins (silence).

Clear HF (Bin 0 to Zero all bins (silence) to the right of the clicked bin. Since the high harmonics
End) are silenced, you can think of this as a low-pass filter.
Clear LF (Start to 0) Zero all bins (silence) to the left of the clicked bin. Since the low harmonics
are silenced, you can think of this as a high-pass filter
Generate Saw Set all harmonic bins to relative amplitudes creating a standard saw
waveform.
Randomize Low x Bins Insert random values for the left-most number of bins. This changes the
base tone of the sound while leaving the higher-frequencies (“buzz”) intact.

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Menu Item Description

Randomize Low x Bins Insert random values for the left-most number of bins, but allows 50%
(with Half) amplitude for harmonics. This provides more tonal options.
Randomize All Randomize all bins. This results in a noisy/buzzy tone. This is useful as
a starting point for further destruction with FFT drawing or other menu
commands.
Create Random Series Randomly remove harmonics.
Gaps
Progressive Fade Reduce the high frequency content gradually. This is useful for bringing back
a natural-sounding tonal balance to an overly bright or buzzy wavetable
without resorting to removing the highs altogether.
Shift Octave Up Spread all bins (1->2, 2->4, and so on) so that the resultant waveform is
doubled in frequency.
Shift Octave Down Same as above, but in reverse.
Repeat Bin Group Create copies of the harmonics from the start to the current cursor location,
(Start to Cursor Pos) repeating all the way through the spectrum.
Draw Even Harmonics Prevent the mouse from operating on odd-numbered bins.
Only
Draw Odd Harmonics Prevent the mouse from operating on even-numbered bins.
Only
Snap Vertical Draw to Snap vertical mouse drawing to exactly 0%, 25%, 50%, 75% and 100%.
Quarters
Scale Freq Values by Amplitude draw/react proportionally to the selected bin, exaggerating higher
Bin Index harmonics visually. Using this feature, a proper sawtooth will be a horizontal
line draw instead of an exponential curve across the harmonics.

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Managing Frames (Subtables)

You can use the Wavetable Editor to perform a wide range of operations on frames within a wavetable.

Managing Frame (Subtables)

Exploring Common Frame Operations

You can access the most commonly used frame operations through a series of buttons and menus
directly below the frame display.

Frame (Subtable) Buttons and Menus

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Copying and Pasting Frames

You can copy one or more frames and paste the contents to a new location in the wavetable.

Start by selecting the frames you want to copy. You can click to select a frame, and Shift-click to extend
your selection. Your selection needs to be contiguous.

Selecting Frames to Copy

Click the COPY button.

Select the starting frame of the destination and click the PASTE button.

The frames appear starting in the target frame.

Pasting Frames into the Wavetable

Inserting and Removing Frames

You can use the REMOVE menu to insert or delete frames. You can also initialize all frames using this
menu.

Click the button and choose an option using the menu that appears. The following table
describes the menu options:

Menu Item Description

Init All (Default) Clear all frames/interpolations. The wavetable is brought to its default state
(a single saw frame).

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Menu Item Description

Insert (at current Add an additional frame to the wavetable set, inserted after the currently-
index) selected frame. This has the same effect as pressing the + button below the
waveform.
Remove (current Remove the currently selected frame. This is the same function as pressing
index) the - button (below the waveform).
Remove: Remove multi-selected frames (Shift-click in the thumbnail area to multi-
multiselection select a range of frames).
Remove: beginning-> Remove the frames from the beginning (1) through the selected frame.
selected
Remove: selected-> Remove the frames from the selected frame through to the end.
end
Remove All (except A “crop” feature, useful when you decide that a single frame or certain range
Selected) (multiselect) is all you want to keep.
Reduce to Thins the number of frames; helpful to easily keep only every nth frame.

Sorting Frames
You can use the SORT menu to reorder existing frames based on a spectral property. Keep in mind that
you can also manually sort frames by dragging the frames left and right within the thumbnail display.

Click the button and choose an option using the menu that appears. The following table
describes the menu options:

Menu Item Description

Sort by spectrum Sort frames based on which frame has the highest peak frequency bin.
(Peak Spect)
Sort by spectrum Sort frames based on where the average spectral content exists (sum of all
(Average Spect) frequencies).
Sort by spectrum Sort frames by the highest overall peak (concentrated frequency energy).
(Peak Amount)
Sort by spectrum ( Sort frames by how many frequency bins contain energy (spectral
Num w/Spect) complexity).
Sort by spectrum Sort frames by the highest frequency bin to contain spectra. This should
(Highest w/Spect) work well for filter sweeps, for instance.
Sort by spectrum Sort frames by the amount of energy in the fundamental. When in doubt, try
(Fundamental Amt.) this sort first.
Sort Randomize Randomize the order of the table indices.
Reverse Entire Table Reverse all frames in the table. This is useful if you decide that you want the
Order table order to become bright-to-dull instead of dull-to-bright, for instance.

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Using the Formula Parser

Use the formula parser to generate a wavetable (single frame or entire wavetable set) from a
mathematical formula. You can use the Formula presets menu containing multiple examples to get you
started.

See “Using the Formula Parser” chapter for more information.

Exploring the Menu Commands

The Wavetable Editor features a set of menus that allow you to quickly and easily manipulate the
waveforms.

Wavetable Editor Menu

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Importing a Wavetable
You can import a wavetable into the Wavetable Editor.

Click the button, and choose an import option in the menu that appears.

A dialog appears allowing you to select a file to load (which overwrites the wavetable set you are
currently editing). Refer to the “Importing Audio” chapter for a detailed description of the options in this
menu.

Keep in mind that you can also drag-and-drop waveforms directly from the macOS Finder or Windows
Explorer. This is often a more convenient way to import sounds.

Exporting a Wavetable
You can export a wavetable from the Wavetable Editor.

Click the button, and choose an export option in the menu that appears.

The following table describes the available options:

Menu Item Description

Export All As 8-bit Export the wavetable in 8-bit format. This saves the wavetable using a file
(.256) format compatible with certain hardware modular synthesizers (such as
Wiard and Piston Honda).
Export All As 16-bit Export the wavetable in 16-bit format. This saves the file in WAV format,
(.wav) mono, 16-bit, 44100 Hz, 2048 samples per subtable.
Note that additional header information for interpolation mode and
interpolation tables are not saved as part of the WAV data.
Export All As 32-bit Export the wavetable in 32-bit format. This saves the file in WAV file format,
(.wav) mono, 32-bit, 44100 Hz, 2048 samples per subtable.
Note that additional header information for interpolation mode and
interpolation tables are not saved as part of the WAV data.
Export All As Single- Export the wavetable as a set of individual single-cycle WAV files.
Cycle Waves
Export Selection Export and save a wavetable using the Serum file format (a WAV file with
extra header information). This is similar to the other save commands, except
that only the selected frames are included in the file.

If you don’t see a format compatible with your needs, you can convert WAV files to an alternate format
using a third party application or utility.

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Single Menu
The SINGLE menu contains process functions that alter the currently selected (visible) frames.

Menu Item Description

Normalize Adjust the waveform to maximum-scale amplitude.

Remove DC Offset Remove any DC (up/down bias to the waveform). This is typically not
needed.
Flip Vertical (Polarity Perform a polarity invert operation (often somewhat mistakenly called
Invert) “phase invert”).
Flip Horizontal Reverse the audio. As a short looping wave, it probably won’t sound
(Reverse) reversed in most situations.
Shift Horizontal to Nudges/wrap the wave so the edges fall on a zero crossing. This isn’t
Zero Crossing essential, but might be useful for applying fades or matching phase among
multiple waveforms.
Init (Silence) Replace the current table with silence.
Fade Edges (Grid Size) Create a fade in at the left edge and a fade out at the right edge based on
the width of the horizontal grid size (set in the lower right).
X-Fade Edges (Grid Similar to above, but instead of fading to the center line, the edges fade to
Size) each other.
Filter (Grid Size) Completely remove upper harmonics using a low pass filter. A lower grid
size means more low pass filtering. You can achieve the same low pass filter
effect using the FFT area (Ctrl/right-click > Clear HF).
Since this uses FFT, it is infinitely steep; you might notice some DC shift as
all DC offset is removed.
Sample Redux at Grid Perform a sample rate reduction for a lofi sound.
Size
The grid size is not used in a literal way but as a means for specifying an
amount (larger number offers more sample redux).
Send to Noise Convert the currently selected frame to a single cycle waveform and import
Oscillator the waveform into the noise oscillator.

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All Menu
The ALL menu offers process functions, similar to the SINGLE menu, but applying to all frames (1-256)
in the wavetable.

Menu Item Description

Normalize Each Individually normalize every frame to its own peak maximum.
(Gained Separately)
Normalize Same (Max The entire wavetable set is scanned for a peak level, and the same gain
From All Frames) amount is applied to each frame.
Remove DC Offset Remove any DC (up/down bias to the waveform). Noet that this is typically
not needed.
Flip Vertical (Polarity Perform a polarity invert operation (often somewhat mistakenly called
Invert) “phase invert”).
Flip Horizontal Reverse the audio. As a short looping wave, it probably won’t sound
(Reverse) reversed in most situations.
Fade Edges (Grid Size) Create a fade in at the left edge and a fade out at the right edge based on
the width of the horizontal grid size (set in the lower right).
X-Fade Edges (Grid Similar to above, but instead of fading to the center line, the edges fade to
Size) each other.
X-Fade Edges (16 Same as above, but only a micro-fade on the edges (16 samples is small!).
Samples)
Filter (Grid Size) Completely remove upper harmonics using a low pass filter. A lower grid
size means more low pass filtering. You can achieve the same low pass filter
effect using the FFT area (Ctrl/right-click > Clear HF).
Since this uses FFT, it is infinitely steep; you might notice some DC shift as
all DC offset is removed.
Remove Fundamental Remove the lowest frequency (pitch), effectively akin to zeroing the top-left
(HPF) bar of the FFT display (fundamental) but for all tables.
The formula “z=(q>1)?in:0” would also yield the same result, or simply
“(q>1)?in:0” if you want to only apply to the currently visible frame.
Remove Low Spectra Remove the lowest frequency bins, somewhat similar to a high-pass-filter.
(Grid Size)
Remove Low Phases Zero the phases on the lowest frequency bins.
(Grid Size)
Sample Redux at Grid Perform a sample rate reduction for a lo-fi sound.
Size
The grid size is not used in a literal way but as a means for specifying an
amount (larger number offers more sample redux).

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Menu Item Description

Resize Tables to be Divide every frame in half to become two frames. This doubles the number
Half (2x Total of frames (so you shouldn’t use this if you have more than 128 frames).
Number)
Resize Tables to be Every frame is grouped with the following frame. This is useful if you notice
Double (½ Total every second frame similar after a WAV import (the frequency was detected
Number) an octave too high).
Create PWM from Remove all frames except the current frame and create a PWM shift across
This Table to All all 256 frames.
There is a real time PWM effect using the WARP knob (main panel), but this
way you can perform pulse width modulation and use another warp effect.
Nudge All Phases for Preserve the phase of the lowest frequency (fundamental) across various
Fundamental to 50% waveforms.
Set Spectra (This Apply FFT bins (spectrum) from the current frame to all frames.
Frame to All)
Set Phases (This Apply the FFT phase information from the current frame to all frames. This
Frame to All) is useful to make all frames match in phases beyond just the fundamentals,
for example, solid/consistent sound during morphing.
Set Spectra from Remove the relative amount of harmonic content contained in the other
Other Osc oscillator.
Set Phases from Apply the FFT phase information from the other oscillator frames (A<>B) to
Other Osc the frames of the visible oscillator.
Subtract Spectra from Subtract harmonic content based on the harmonic content of the other
Other Osc oscillator’s wavetable.
Blur Spectra - Interpolate (smooth) the harmonic content between adjacent harmonics. The
Adjacent Bins grid size value determines how many neighboring harmonics are factored
(Grid Size) into the smooth operation.
Blur Phases - Interpolate (smooth) the phase content between adjacent harmonics. The
Adjacent Bins grid size value determines how many neighboring harmonics are factored
(Grid Size) into the smooth operation.
Blur Spectra - Interpolate (smooth) the frequency content between adjacent frames. The
Adjacent Frames grid size value determines how many neighboring harmonics are factored
(Grid Size) into the smooth operation.
Blur Phases - Interpolate (smooth) the phase content between adjacent frames. The grid
Adjacent Frames size value determines how many neighboring harmonics are factored into
(Grid Size) the smooth operation.
Shift Horizontal to Move the audio data to the right to have the left edge of the frame begin
Zero-Crossing at a zero crossing (where the waveform polarity changes from negative to
positive).

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Morph Menu
Use the MORPH menu to create or remove interpolation frames between existing frames. Note that
you must have more than 1 and less than 256 frames.

After selecting a morph item from the menu, you’ll notice that there are now 256 frames in the WT
POS selector. This is because all empty wavetable slots are now filled with interpolated (blended)
waveforms of the neighboring tables.

You’ll also notice that the thumbnails no longer display “1, 2, 3”, and so on, but rather “1, 17, 33” (or
similar). This is because the intermediate tables (for example, 2-16 in this example) contain the newly-
created morph tables.

You’ll see these intermediate tables in the waveform area as WT POS is adjusted, but they don’t exist as
thumbnails.

After you exit the Wavetable Editor and return to the main panel, you’ll also notice the interpolated
frames appear gray in the 3D wave overview (whereas green shows the “real” frames, and yellow shows
the currently-selected frame).

Menu Item Description

Morph - Crossfade Create interpolated frames by crossfading the neighboring frames together.
This is the recommended default, and what traditional wavetable synths do.
Morph - Spectral Use the spectral and phase content of neighboring frames to re-synthesize
the interpolated frames. This is what additive synthesizers do.
Morph – Spectral Same as Morph - Spectral, but the phase content of the fundamental is
(Zero Fund. Phase) zeroed for all source frames. This way the lowest frequency does not shift/
rotate between frames.
Morph – Spectral Same as Morph - Spectral, but all phase content is discarded. This might alter
(Zero All Phases) the sound of the source content drastically, and therefore can sometimes be
undesirable.
However this option also creates the smoothest transitions between frames
since no frequencies need to shift phase.
Remove Morph Tables Revert back to how things were before interpolation was applied.
Note that clicking “Undo” might be the better choice for reversing the morph
since, in the case of the spectral (zero-phase) modes, the two zero-phase
choices destructively alter the source tables.

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Saving Wavetables
If you have modified one or more frames in the Wavetable Editor, the wavetable name changes to a
tinted background indicating that the wavetable has been modified but not yet saved to storage.

Wavetable Modified

Right-click Custom and choose Save Table in the menu that appears.
Choose the file name and location in the dialog that appears.

Save your wavetables in the User folder and, if at all

possible, do not overwrite factory wavetables (or else the
presets may sound different). Also, when in doubt, always
pick a new name.

Note that you do not need to save your wavetables explicitly. Serum
always saves changes you make to wavetable data inside a preset (your
song) unless it is a factory wavetable. This uses some hard disk space
— how much depends on how many frames you use in the wavetable,
from 8k to 4 Megabytes

The benefit, however, is that you can exchange presets with others, or
open your song in the future, without having to worry about table file
management. The only reason to explicitly save a wavetable is to have it
appear in the Wavetable menu.
Saving a Wavetable

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Importing Audio as Wavetables
A great way to obtain high-quality source material for wavetables is by importing audio data. This can be
done using various methods, which can generally be categorized as either single-cycle and multi-cycle
imports.

It’s important to realize that wavetables do not behave like samples in a sampler. When importing
audio to create a wavetable, you shouldn’t expect to create ultra-realistic reproductions of acoustic
instruments. Use Sample mode (in any of the oscillators) to work directly with source samples.

Understanding Multi-cycle Waveforms

Most real sounds you come across (such as speech) consist of multiple waveform cycles. In a human
voice waveform, you can see the repetitive nature of sound, which becomes the pitch we hear. You’ve
likely seen this before when manipulating audio in a DAW.

Samplers typically play audio as a single stream of data. In contrast, when importing a sound into Serum,
it attempts to slice the sound into individual single-cycles. Because of the nature of audio, it’s generally
best to select source sounds that are monophonic (that is, sounds that contain a single pitch). This
means that, in most cases, a single note is better than a chord.

Because these single cycles become the basis of the oscillator, pitch information is effectively removed.
In other words, if you load a sound that has a pitch bend, the pitch bend will no longer exist. However,
wavetables have their own set of advantages, which one could describe as a “solid” or “fixed” sound that
lends itself well to unison and wave manipulation (sync, FM, and more) without sounding flimsy.

Serum therefore does a fantastic job of importing the waveform of other sounds. Fixed-pitch, one-
shot (monophonic) sounds, such as a one-shot sample of a synthesizer, are among the best choices for
importing into Serum. Speech and other complex sounds can however yield some pretty interesting
results if you’re open to some experimentation.

Importing Multi-Cycle Waveforms

To import a multi-cycle WAV file, drag the audio file from the macOS Finder, Windows Explorer, or host
DAW file browser to the waveform display on Serum’s main window.

Note: Dragging files directly from the host arrangement window or “region bins” is not possible in most
hosts, but using the host’s standard file-browser should work. In addition, many hosts are able to show
the (parent) sound file in the host file browser, and you should be able to drag from there.

When importing stereo files as a wavetable, Serum uses the left channel in OSC A and
OSC C, and uses the right channel in OSC B.

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Import Audio Options

As you drag the waveform, you’ll see several options appear. The location where you release the
mouse determines the import method. Serum then analyzes the sound and creates a new wavetable in
memory. The analysis specifics depend on the import method you choose.

The following describes the import options:

• DYNAMIC PITCH - ZERO SNAP

Serum scans the audio file and builds a pitch map. Serum then attempts to locate zero-crossings
within the pitch map. While this works well with simple sounds, complex sounds typically don’t
adhere to sensible zero crossings, so you’ll end up with at least some glitches at best.

Use this mode when you have a sound with a non-fixed fundamental (pitch bend or vibrato) and
the sound is pretty simple, for example a sawtooth wave with little filter sweep/resonance.

• DYNAMIC PITCH - FOLLOW

Similar to the previous option, Serum builds a pitch map and imports a varying-sized segment of
audio for each frame (subtable) based on the analyzed pitch.

Unlike the previous option, pitch follow import does not attempt to locate zero crossings. This
option is therefore better suited for complex sounds, such as a source sample that might have a
touch of chorus/unison, resonance, or background noise/notes.

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• FREQUENCY ESTIMATION

Serum analyzes the incoming waveform to determine its dominant frequencies and harmonic
content, and uses this information to convert the audio into a wavetable. This involves analyzing
the audio signal to identify the fundamental frequency, and then determining the harmonics
(integer multiples of the fundamental frequency).

By matching the detected fundamental frequency to a musical pitch (for example, C4 or A3), Serum
can align the wavetable content to the correct pitch. Serum then uses the estimated frequencies
to guide the conversion of the audio signal into a series of wavetable frames. This ensures that
the harmonic structure and frequency content of the original audio are preserved within the
wavetable, maintaining the character of the original sound.

Frequency estimation is particularly beneficial for audio samples with well-defined pitches and
harmonic structures. These types of samples allow Serum to accurately extract fundamental
frequencies and harmonics, making it easier to convert the sounds into expressive and playable
wavetables. Examples include monophonic synth leads, bass sounds, vocals with sustained notes,
plucked and struck instruments, and FM (frequency modulation) generated sounds.

• Constant framesize (PITCH AVERAGE)

If in doubt, try this one first!

This option is typically the best choice when a sound has a fixed frequency, such as a one-shot
from a synthesizer (in other words you hear it as a perfect or near-perfect constant pitch, with
essentially no pitch bend or vibrato).

In this mode, Serum analyzes the entire file for an average pitch, and then uses this number of
samples as the import length. Because some sounds contain half-cycles, silence, multiple notes,
and other artifacts, Serum might not correctly guess the desired pitch.

Fortunately, Serum displays the number of samples it is using per frame in the Wavetable Editor
formula area and switches over to this “fixed” value found during analysis (unless changed or
cleared from the Formula field).

• FFT 256/512/1024/2048

FFT, or Fast Fourier Transform, is a method that converts a signal from the time domain to the
frequency domain, revealing its frequency components. It efficiently breaks down a complex
waveform into individual sinusoidal frequencies, enabling analysis of amplitude and phase at
different frequencies.

Unlike the other import modes, which import and divide (and possibly stretch) chunks of the
original waveform, the FFT modes are a spectral import. This means that these import modes
divide the source audio into small snippets of time, and analyze the spectral content.

One way of thinking of this is a “blurred averaging of the frequency content”. This can be very
useful for sounds such as drum loops, speech, and other material where you want the flavor of the
sound for abstract purposes.

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The numbers 256, 512, 1024, and 2048 represent the number of samples used to perform the
FFT analysis. FFT 256, for example, analyzes 256 samples at a time.

Larger FFT sizes, such as 1024 or 2048, provide higher frequency resolution because more
samples are considered during the transform. This means you get a more detailed breakdown of
frequency components, making it better for detecting specific tones and harmonics.

Smaller FFT sizes, including 256 and 512, provide lower frequency resolution, which results in a
broader view of the frequency spectrum. This can be less detailed but faster in terms of processing.

• Switch OSC type

You can choose to import the audio as a regular sample, automatically switching to the Sample,
Granular, or Spectral oscillator modes. In these cases, the audio is imported directly without
creating a wavetable.

Advanced Imports
Due to the complex nature of audio signals, using a pitch average might not always be perfect.
Sometimes you might want to specify the exact number of samples for each cycle (that you can measure
yourself in a sample editor).

The Wavetable Editor includes a formula parser (described in the next chapter) featuring a text box with
the placeholder text “(enter formula)”. Although the primary function of this field is to create waveforms
from functions, you can also type the following:

• A one to four-digit number (such as 1024) to instruct Serum to split the sound file into segments
with this number of samples.

• A MIDI “note name” (such as B0, C#2, D6, and so on).

Serum converts the sound file into the appropriate nearest number of samples (rounding to the
nearest whole number of samples).

This MIDI note/sample conversion assumes a 44,100 Hz source sound file. If your source sound
file is not 44,100 Hz, the number of samples is still held true, but you should disregard the
displayed frequency/note information in the formula text area.

Note: Since musical note frequencies are not often perfectly divisible by a sample rate, many pitches will
have some visible “drift” on import.

When creating a wavetable from imported audio, you might hear undesirable buzz from
subharmonics or other factors caused by the beginning and end of the wave cycle not lining up
perfectly.

Therefore, after importing using one of the above methods, try using a fade command from the
Process menu. For example, X-Fade Edges (16 Samples) or X-Fade Edges (Grid Size) should
give you a less buzzy-sounding result.

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Text File Overrides for Specific Results (Advanced)

When dragging an audio file to import, Serum notes the location of the file you dragged and then looks
for a file with the same name but with a .txt file extension containing audio file information.

For example, if your audio file is sound.wav, Serum looks for the sound.txt file. If Serum can’t
find the matching file, Serum then looks for the FolderInfo.txt file in the same folder. The
FolderInfo.txt file contains information that applies to all sounds in the folder; this saves you from
having to duplicate the same text file for every WAV file in the folder.

The format of the text file is very basic.

The first line specifies the number of samples-per-cycle of the audio file (in square brackets). Valid
values are numbers between 32 and 9999. The second line specifies whether to create intermediate
interpolated tables. The default is yes; use [no interp] to specify the opposite.

The following table shows some examples:

Samples per Second Description

[512] Specifies a 512 samples-per-cycle waveform with crossfade interpolation.

[768] Specifies a 786 samples-per-cycle waveform with crossfade interpolation.
Note that the second line is optional, since it is the default.
[interp]
[1024] Specifies 1024 samples-per-cycle with no interpolation.
[no interp]

Internally, Serum uses 2048 samples for each single-cycle. This makes 2048 the ideal
number of samples to use as a wave cycle if you plan on generating sounds from
synthesizers, vocoders, and so on, to import into Serum (because no resampling of the
source audio is needed).

This 2048 samples-per-cycle works out to 46.875 Hz at 96000 KHz sampling rate
(96000/2048 = 46.875), which is F#0 +24 cents. Since the octave might differ in various
hosts and synthesizers, render and measure in a program that allows you to select in
samples, such as the freeware sound editor Audacity).

Type 2048 in the Formula field prior to dragging to import. Serum will then not have to
alter the sample data at all.

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Importing Single-Cycle Waveforms

To import a single-cycle waveform, (or import a short sound to be interpreted as such), drag an audio file
from the macOS Finder, Windows Explorer, or the host DAW file browser to the corresponding frame
thumbnail in the Wavetable Editor.

Importing a Single-Cycle Waveform

This replaces the waveform in the specific frame; the rest of the wavetable remains untouched.

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Single-Cycle Waveform Imported

To import multiple single-cycle waveforms at once, drag them together to the oscillator waveform view.

Serum notices that you dragged multiple files and

treats them as single-cycle waveforms.

This replaces your current wavetable with a new

one that consists of the files you dragged.

Importing Multiple Single-Cycle Waveforms

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Using the Import Menu

The Import menu in the Wavetable Editor offers the same import options as the drag-and-drop
operation. Use this method if you prefer a standard file browser dialog instead of dragging and dropping
files.

Importing Audio using the Import Menu

Creating a Sound Specifically for Serum Import (Advanced)

Use this procedure when you want to import a waveform (sound) into Serum with maximum quality
from another synthesizer to use as a wavetable.

Whenever possible, use low-frequency notes. Also, use 2048 samples-per-cycle, which
precludes the need for Serum to interpolate the sound.

Alternatively, use low C at 44,100 Hz (33 Hz, 1349 samples per cycle). This is slightly easier
to set up since no fine tuning of pitch is needed.

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The following procedure shows an example of how to export a 2048 samples-per-cycle wave from
another synthesizer and import it into Serum.

1. Determine the appropriate source note (pitch).

Open the Serum Wavetable Editor and type 2048 into the Formula text box. Serum displays the
following in the field:

split at: 2048 samples (22 Hz, note: F1 and -22 cents)

This suggests that you play a low F with -22 cents to create the proper length of 2048 samples per
cycle.

2. Render a file playing this pitch from the other synthesizer.

Do the following:

a. Create the F1 note in your host sequencer piano roll on the synthesizer track.

Note that octave naming might be different since, unfortunately, there is no standard. You should
probably use a spectrum analyzer to verify ~22 Hz is the fundamental, not ~11 Hz or ~44 Hz.

As for the duration of the note, since Serum can handle 256 wave cycles, you can render this
22 Hz file for up to 11.6 seconds, which is about 8 bars at 165 BPM. If, on the other hand, the
sound has very little modulation/change, there is no need for such a long note. You can probably
determine by ear when the source sound has stopped changing; there is no need for a longer note.

b. Set the fine tuning to -22 cents.

How you do this varies depending on the synthesizer. Typically, this is set per-oscillator, but some
synths have a global tuning.

If you can’t do this in the source synth, consider adding the appropriate amount of “pitch bend”
down as a MIDI message (22% down if pitch bend range is 1 on the source synth). A=440 to
approximately A=434.5 Hz is another potential option.

c. Render (export) this note from the synth as audio. Alternatively, you can freeze and flatten to
produce the synth note as an audio file.

3. Drag the rendered audio file into Serum.

If the value 2048 is no longer visible in the Formula text field (for example, if you closed the Serum
window after starting this procedure), type 2048 into the field.

When you release the mouse, the audio is imported. The source audio file (render) is no longer
needed at this point unless you wish to re-import it into Serum with different settings.

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Note the following:

• You will likely have blank or unnecessary tables at the end of the wavetable.

Using the thumbnails, find the first table you don’t want to include. Click the button
and choose Remove: Selected->End in the menu that appears.

• You might want to apply fades to the tables (use one of the Fade or X Fade options using the
Wavetable Editor Process menus) to eliminate any buzzing artifacts from frame edges.

If your source sound has no subharmonic content, this shouldn’t be necessary.

• Listen to the entire wavetable set by playing a note and dragging the WT POS number box in the
Wavetable Editor (or, similarly using the WT POS knob on the main panel for the oscillator).

Alternatively, for automatic playback, you can use a mod source (for example, an envelope with
long attack or an LFO with an upward saw shape) to modulate the wavetable position.

Importing an Image File as a Wavetable

One of the most experimental ways to create a wavetable in Serum is to import an image file. When
importing the file, Serum automatically maps the pixel luminance to the amplitude, creating largely
unpredictable results that can sometimes lead to happy sonic accidents.

The process is extremely simple.

Drag a PNG file (8-bit depth) from the

Finder (macOS) or Explorer (Windows) to a
wavetable oscillator.

This can be either a color or grayscale image.

The width of the image (in pixels) determines

the number of frames in the wavetable (to a
maximum of 256).

In a grayscale image, black (luminance value

0) represents silence (no amplitude). White
(luminance value 255) represents maximum
amplitude.

Shades of gray interpolate between these

extremes.

In general, gentle gradients create smoother

waveform transitions. Unique shapes produce
genuinely experimental sounds.

Importing a PNG File

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The first frame of the wavetable appears in

two dimensions.

As expected, the waveform has no

recognizable relationship to the source image.

Imported Wavetable (2D View)

Switching to 3D however can sometimes

show a slight semblance.

Open the Wavetable Editor to further

process the wavetable. You can normalize
the frames (to ensure that the frames are
balanced), crossfade edges (to smooth
transitions between frames), and filter the
frames, among other operations.

See “Using the Wavetable Editor” on page

274 for detailed information.

Imported Wavetable (3D View)

To automate a sweep
through the wavetable,
draw an LFO ramp and
drag the LFO tab to the
WT POS knob.

This modulates the

wavetable position
moving from frame 1 to
256.

LFO Ramp

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Embedding Wavetables When Saving a Preset

When saving a preset that includes a custom wavetable created from imported audio, Serum saves the
file path of the audio sample along with the preset. By default, Serum does not store the audio sample
(and corresponding wavetable) within the preset file itself.

This means that if you move the audio sample to a different location on your drive, Serum will not be
able to locate the file automatically. When you try to load a preset that has missing audio files, Serum
displays a dialog similar to the following:

Missing Files Dialog

You have two options. Do either of the following:

• Copy the missing audio file to a folder within the current search path and click the
button.

• Click the button to include the folder containing the audio file in the search path, then click
.

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 Importing Audio as Wavetables

To simplify file management, Serum also allows you to embed the wavetable generated from the
imported audio into the preset when saving.

After importing the audio file and creating the

custom wavetable, close the Wavetable Editor and
return to the oscillator display.

Click the button (near the top left of the

oscillator display).

The button becomes enabled.

Alternatively, click the menu and choose Embed in

Preset.

This has the same effect and enables the

button.

Save the preset.

The custom wavetable is now saved with the

preset. You no longer need to manage the location
of the audio file.
Embed in Preset

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Using the Formula Parser
You can use the Formula parser to make a sound using math!

Specifically, the Formula parser field allows you to enter math functions to plot tables in a generative
fashion. This is a fairly advanced feature; don’t worry if you don’t follow all the details. You can still
explore this capability through experimentation.

However if you want to generate waveforms from thin air and enjoy this kind of approach, you’ll be glad
that you paid attention in math class!

The good news is that Serum includes many formula presets, and it’s easy to paste formulas created by
other users.

Basic Functions
The following table lists the basic functions supported by the parser.

Name Arguments Description

sin 1 sine function

cos 1 cosine function
tan 1 tangent function
asin 1 arcus sine function
acos 1 arcus cosine function
atan 1 arcus tangent function
sinh 1 hyperbolic sine function
cosh 1 hyperbolic cosine function
tanh 1 hyperbolic tangent function
asinh 1 hyperbolic arcus sine function
acosh 1 hyperbolic arcus cosine function
atanh 1 hyperbolic arcus tangent function
log2 1 logarithm base 2
log10 1 logarithm base 10
log 1 logarithm base 10
ln 1 logarithm base e (2.71828...)
exp 1 e raised to the power of x
sqrt 1 square root of a value

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Name Arguments Description

sign 1 sign function -1 if x<0; 1 if x>0

rint 1 round to nearest integer
abs 1 absolute value
min var. minimum of all arguments
max var. maximum of all arguments
sum var. sum of all arguments
avg var. mean values of all arguments

Built-in Binary Operators

The following table lists the default binary operators supported by the parser.

Operator Meaning Priority

&& logical and 1

|| logical or 2
<= less than or equal 4
>= greater than or equal 4
!= not equal 4
== equal 4
> greater than 4
< less than 4
+ addition 5
- subtraction 5
* multiplication 6
/ division 6
^ raise x to the power of y 7

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Constants and Variables

The following table lists the constants and variables supported by the parser.

Note the following:

• sel refers to the current (existing) waveform value of the selected table

This does not change for each table when using a multi-table formula. In other words, the formula
contains y or z, and refers only to the selected table when formula processing begins.

• rand is a random number from -1.0 to 1.0

This value stays the same for all tables.

Symbol Description

pi 3.141592658979323846264338
e 2.718281828182818281828
w The current time-value getting plotted, from 0.0 to 1.0. This is the same as
(x+1)/2.
x The current time-value being plotted, from -1.0 to 1.0.
y The current table number, from 0.0 to 1.0.
z The current table number, from -1.0 to 1.0. This is equivalent to (y\*2)-1.
q When a q is present in the formula, the function plots to the FFT bins
instead of plotting to the waveform display. Note that q iterates from 1 to
512 for the respective harmonics/bins.
in The current (old) visible waveform value of the plotting table. This changes
to each old table, if using y or z, which plots all tables.
sel Similar to in, but only the currently-selected wavetable (does not change to
each table; uses the selected table when formula processing begins).
rand A random number from -1.0 to 1.0 that stays the same for all tables
(precalculated for every time position).

Note the following:

• y and z refer to the current table number. Therefore, when y or z is in the expression, all tables for
the current oscillator are regenerated.

• q renders the function to FFT instead of to the waveform display. There is no reason to include x
or y in a formula containing q.

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 Using the Formula Parser

Exploring the Formula Presets Menu

Serum offers a formula presets menu that you can use to get started with preset examples. This
provides a good way to learn the capabilities, as well as to create your own presets.

Formula Presets Menu

As soon as you select a formula, it appears in the Formula field automatically and the waveform is
calculated.

Menu Item Description

Singles These are single-cycle formulas that do not contain y or z variables. When
you select an option, only the currently-selected table is replaced/generated
with the formula.
Multis These are multi-cycle formulas that contain y or z variables. When you select
an option, the entire wavetable is replaced.
User Singles These are user-defined single-cycle formulas.
User Multis These are user-defined multi-cycle formulas.

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 Using the Formula Parser

Saving Your Own Formulas

You can save your own formulas for quick access.

1. Type the formula in the Formula field and press the Enter key.

2. Click the formula presets menu and choose Save Formula in the menu that appears. A dialog
appears allowing you to save the formula.

Save Formula Dialog

By default, the text box displays the formula.

3. Type the name of the formula and click the button.

The formula is saved in the corresponding formula sub-menu (either User Singles or User Multis,
as appropriate). You can now access your formula using the formula presets menu.

Managing Formula Files Manually (Advanced)

Serum uses two files to store the user formula presets:

• FormulaUserMultis.txt

• FormulaUserSingles.txt

You can find these files in the Serum 2 Presets/System/ folder. The text files have the following
format:

[formula1][formula1-name]

[formula2][formula2-name]

You can find existing examples in the FormulaFactorySingles.txt or

FormulaFactoryMultis.txt files.

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 Using the Formula Parser

If you need to remove a formula preset that you saved earlier, do the following:

1. Open the appropriate user formula preset file using a text editor.

2. Delete the line containing the formula you want to remove.

3. Save the text file.

Important: While you can also edit the FormulaFactorySingles.txt and

FormulaFactoryMultis.txt files, it’s better only to use the user files listed in this section instead.
This prevents your personal formulas from being overwritten when you install a Serum update.

Exploring Formula Parser Examples

This section shows a set of examples of using the q variable in formulas. When you include the q
variable in a formula, Serum processes the formula using the FFT area instead of directly “as audio” in
the wavetable display (time domain).

This means you can do signal generation or processing of a wavetable in the frequency domain. In this
case, the q value represents the bin number in the FFT area at the top of the Wavetable Editor, from 1
to 512.

For example, consider the following formula:

q<17

The formula creates a wavetable frame with only the first 16 harmonics.

Formula as q<17

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As another example, consider the following formula:

q<z*256

This formula creates an entire table set of 256 frames, with one additional harmonic in each
consecutive frame.

Next consider the following formula:

(1/q)^0.25

This creates a sawtooth wave with higher harmonics than a normal saw (-3 dB/oct). Replace the 0.25
value with a different number to alter the spectral decay (for instance, 0.5 produces a normal saw, 0.75
creates a duller saw).

Alternatively, you could replace 0.25 with z, as shown in the following:

(1/q)^z

This causes Serum to create 256 frames in the wavetable with the harmonic scale.

Finally, consider the following formula:

((q%2)==1)?in:0

This formula removes every second harmonic (even harmonics) from the current wavetable frame,
leaving odd harmonics only (like a square wave).

Formula as ((q%2)==1)?in:0

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Using this on a (default) sawtooth wave results in a square wave. This is a popular formula, particularly in
Dubstep bass sound design, to make tables sound more “hollow” (taking up less of the spectrum).

Note: This formula appears as an included preset called Proc:Squarify.

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Exploring Global Settings
You can use the GLOBAL module to configure global settings in Serum.

There are two types of global settings: those saved with your preset, song, or patch, and those saved as
part of Serum, accessible to all presets.

Serum Global Settings

Using the Global Module

Click the GLOBAL tab to access the module.

Accessing Serum Global Settings

The global settings page appears.

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 Exploring Global Settings

The page is divided into the following panes to help you quickly find the appropriate settings:

• Preferences — Specify global preferences including user interface and MPE settings

• Voice Control — Define the behavior of each voice across the available oscillators

• Quality — Set the render quality and Serum 1 compatibility

• Tuning — Set the concert pitch and manage Serum tuning

The settings page also displays the current Serum version and build date.

Preferences
Use the PREFERENCES pane
to configure your global
preferences in Serum.

This includes default

waveform display, user
interface options, and
double-click
behavior, among other
settings.

Serum Global Preferences

The following table describes the preferences you can set.

Category Preference Description

User Interface Help Tooltips Display tooltips after hovering the mouse
pointer over a control for a moment.
Param value tooltips Display numeric values (as a small pop-up)
when modifying a control.
Double-click params Specify whether double-clicking a control
resets the control to the default (init) value
or whether double-clicking displays a pop-up
text box allowing you to type a specific value.

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 Exploring Global Settings

Category Preference Description

User Interface Mouse wheel param control By default, moving the mouse wheel adjusts
(cont.) the knob that the cursor is currently hovering
over. If you don’t want this capability, enable
this setting to deactivate the feature.
Keyboard shortcuts Set whether Serum should respond to input
from the computer keyboard. Disable this to
prevent Serum from stealing keyboard focus
from your DAW.
Default waveform view The default waveform view in the OSC
panels, either 2D (default) or 3D.
MPE MPE enabled by default Specify whether MPE mode is enabled when
a new instance of Serum is added to your
project.
MPE Pitch Bend (also) By default, Serum maps MIDI pitch bend
maps to Expr X messages to per-note pitch bend and CC10
(pan) messages to note expression X.

Some MPE controllers use the X axis (left/

right movements) to control pitch and will
therefore transmit pitch bend messages.

Select this option to have these gestures

mapped to note expression X in Serum, as
well as to per-note pitch bend.
MPE Expr Y acts Specify whether note expression Y is treated
bi-directional as unipolar or bipolar. This allows you to
match how your DAW or MPE controller
treats note expression Y.
General Limit Mod depth on drop When a modulator source is dropped on a
(based on knob value) knob, reduce the range amount (if needed)
so that the modulation does not exceed the
maximum value for the range.

For instance, if you drag a modulator to

an oscillator LEVEL knob set at 75%, the
assigned modulation depth will only be 25%
(so that a maximum modulator will have
volume reach exactly 100%).

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 Exploring Global Settings

Category Preference Description

General (cont.) Mod Wheel -> WT Pos When the Wavetable Editor is active, the
(when WT Editor is open) mod wheel scans the indices from 1-256.
Silence note + FX tails when Mute effects and any sustaining notes when
host transport stops the host DAW is stopped.
Load MIDI Map from Normally, Serum loads a default MIDI CC
Presets map if the Serum 2 Presets/System/
MIDI CC Maps/Default.SerumMIDIMap is
found, in the following cases:

• When creating a new instance of Serum

• When selecting the Init preset
• When loading a preset
When the Load MIDI Map from Presets
option is enabled, loading a preset causes
Serum to load the MIDI CC mapping that
was saved with the preset instead of the
default.

You might want to enable this option if you

have a specific mapping for FX parameters
that you want to recall, for instance.
Use Ultra quality when Instruct Serum to perform an offline render
rendering (bounce) using ultra quality mode. This
results in the highest quality playback of the
rendered sound.
Since the rendering is performed offline, the
performance trade off in using ultra quality
mode for renders generally makes sense.
Automatically check for Enable to ensure that you are notified when
updates new versions of Serum become available.

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 Exploring Global Settings

Setting the Voice Control

You can specify voice control
settings for Serum to define the
behavior of each voice across the
available oscillators.

Select the oscillators to which the

voice control settings apply. By
default, all oscillators are selected
(green).

Select the Oscillators

Voice Control Settings

Loading a Preset
You can optionally load a factory
supplied or user-defined preset.

Click the voice control (topmost)

field and choose a preset using the
menu that appears.

The configuration loads and

populates the relevant settings.

Voice Control Menu

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 Exploring Global Settings

Creating a New Configuration

You can create a new configuration, or reinitialize the voice control, at any time.

Click the voice control field and

choose Init in the menu.

This initializes the voice control to

the default settings and provides
an opportunity for you to create a
new configuration.

Initializing the Configuration

Configuring the Voice Control

Click one of the numbers, from 1
to 8, to set the sequence length.

Select one of the SEQ controls and

adjust the per voice settings.

Continue setting the other

controls, as appropriate.

Per Voice Settings

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 Exploring Global Settings

Setting Randomization
You can set the randomization for
the PAN, DETUNE, CUTOFF, and
ENVS (envelopes).

Click the corresponding RANDOM

field and drag to set the value. You
can also double-click the field and
type a value.

Setting Randomization

The following table outlines the randomization effect:

Field Description

PAN Randomizes the stereo position, per voice (as a percentage).

DETUNE Randomizes the tuning offset, per voice (in cents).
CUTOFF Randomizes the filter cutoff, per voice (as a percentage).
ENVS Randomizes the envelope offset, per voice (as a percentage).

Setting the Scaling

You can set the scaling for all
envelopes and LFOs.

To set the scaling for all envelopes, Scaling Settings

click the field and drag up or down.

You can use the arrow keys to fine tune the setting. You can also double-click the field and type a value.

This is useful if you change the BPM (beats per minute).

To set the LFO scaling, click the field and drag up or down. You can use the arrow keys to fine tune the
setting. You can also double-click the field and type a value. Choose to set by percentage or rate.

This is helpful for creating many simultaneous pattern changes.

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Saving the Voice Control Settings

Click the button to save the voice control settings. A dialog appears allowing you to specify a
name.

Setting the Quality

You can specify the quality
(oversampling) in Serum.

You can further disable smoothing, as

needed, and enable Serum 1 preset
compatibility.

Choose the oversampling quality settings Quality Settings

using the drop-down menu.

Draft quality sets 1x oversampling (no

oversampling). High quality sets 2x
oversampling, while Ultra results in 4x
oversampling.

Click the button to lock the

quality settings, even when you load a
new preset.

This means that when locked, Serum

ignores the quality configuration in the
preset and uses the settings that you Quality Settings
have locked.

You can also set the following quality settings:

Setting Description

S1 Compatibility Serum 2 features a completely rebuilt sound engine. However, when you
Mode load a Serum 1 preset, this option is automatically enabled to preserve
maximum sonic similarity with Serum 1.
Disable this option if you prefer that Serum 1 presets instead take advantage
of the DSP updates available in the Serum 2 sound engine.

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 Exploring Global Settings

Setting Description

Disable Smoothing Disable automation parameter smoothing.

While Serum is built to try to avoid clicks and jumps in the signal, there are
times when you might want precision over parameter changes (for instance,
during fast rhythmic automation). In this case, you can choose to disable
smoothing (Serum supports sample-accurate automation).
Note: Smoothing also applies to parameter changes effected through mouse
actions on on-screen controls.

Setting the Tuning

You can specify the tuning for Serum, including setting the concert pitch and managing tuning using a
tuning file.

Setting Concert Pitch

Concert pitch is the standard reference
pitch used to tune musical instruments.

The most widely accepted concert

pitch is A4 at 440 Hz, where the A4
refers to the A above middle C (the
Tuning Settings
fourth A key on a piano).

To set the concert pitch for Serum, click the left field and drag up or down. You can use the arrow keys
to fine tune the setting. You can also double-click the field and type a value.

Using a Tuning File

You can also set the tuning using
a tuning file. Serum offers two
options.

You can load a tuning file for the

current instance of Serum, or you
can have the Serum instance
follow the tuning specified
elsewhere in your project using
MTS-ESP.

To set the tuning file for the Serum

instance, click the TUN FILE field Tuning Menu
and choose Load Tuning in the
menu that appears. A dialog appears allowing you to locate the appropriate tuning (.tun) file. To clear the
tuning file, use the same menu and choose Clear Tuning in the menu.

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Using MTS-ESP to Set the Tuning

You can load a separate tuning file for each instance of Serum (using the procedure described in the
previous section). However, if you would like to use a single main tuning file across all instances, Serum
supports the MTS-ESP microtuning system developed by ODDSOUND (www.oddsound.com).

Using the free MTS-ESP MINI plugin, you can load .scl, .kbm or .tun files and automatically retune
all connected MTS-ESP clients (including Serum). This allows you to retune any number of supported
virtual instruments from a central location without requiring you to tune each instrument separately.

MTS-ESP support is enabled in Serum by default. You can disable this feature by unchecking the Enable
MTS-ESP menu option.

Enable the MTS-ESP Note-On Only option to have the tuning set on Note-On MIDI events. This
ensures that the tuning of a note will not change during its duration, even if the global MTS-ESP tuning
updates.

Note the following about using MTS-ESP:

• Loading a .tun file always takes precedence over MTS-ESP. This allows you to tune any Serum
instance differently from the global MTS-ESP tuning.

• If the oscillator pitch mode is set to Steps (set by right-clicking an oscillator OCT or SEM control),
you can pitch oscillators up or down in “periods” and “steps” as defined by the active MTS-ESP
tuning, rather than in octaves or semitones.

In addition to the free MTS-ESP MINI plugin, you can choose from among the following additional
MTS-ESP plugin options:

• Wilsonic MTS-ESP

• Surge XT

• Entonal Studio

• Infinitone

Locking the Tuning Configuration

Click the button to lock the tuning configuration, even when you load a new preset.

This means that when locked, Serum ignores the TUN file and the concert pitch setting in any new
preset that you load.

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 Exploring Global Settings

Checking the Build Version and Date

You can quickly check the version of
Serum that you’re running using the
Xfer pane.

Be sure to refer to this version number

if you reach out to Xfer Records for
technical support.

Serum Build and Date

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Appendix A: Using the Main Menu
You can use the main menu to complete operations that affect the overall performance and capabilities
of Serum. These operations include managing presets, initializing modules, rendering waveforms,
configuring MPE settings, and more.

You can access the main menu near the top right of the Serum window.

Serum Main Menu

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 Appendix A: Using the Main Menu

The following table describes each menu item:

Category Options Description

General About Display Serum release information.

Read the manual Display this manual, the Serum User Guide (PDF).
Check for updates Display whether an update is available, with a link to
the website.
Initialization Init Preset Initialize Serum to allow you to create a new patch.
Init LFOs + LFO Mods Initialize just the LFOs and LFO modulations
Init Modulations Initialize just the modulation assignments, leaving
everything else untouched (including the LFOs).
Presets Load Preset Load a preset from storage. A system dialog appears
allowing you to locate the preset file.
Revert to Saved After loading a preset and making changes, revert to
the saved preset.
Save as Default Preset Save the current preset to the following file:

Serum 2 Presets/Presets/User/
default.SerumPreset
Note that if you are running the Serum FX version,
this saves to the defaultFX.SerumPreset
file. This allows you to configure different default
configurations for Serum and Serum FX.
When you load Serum FX, it will look for the
defaultFX.SerumPreset file. If the file isn’t
found, Serum FX instead looks for the
default.SerumPreset file.
Import Import Preset Pack Import a Serum preset pack. A system dialog appears
allowing you to locate the preset pack.
Rendering Render OSC Warp Use the current wavetable frame of the selected
oscillator and create 256 frames (subtables) spanning
0 to 100% of the WARP knob.
Resample to Play a note of the preset for one bar and capture
(render and import) the result as a wavetable in the
selected oscillator (or OSC A and OSC B).
Folders Open Serum 2 Presets Display the Serum 2 Presets folder using the Finder
Folder (macOS) or Explorer (Windows).
Rescan Folders on Rescan the Serum 2 Presets folder.
Disk
Do this when you make changes to the folders
outside of Serum (using the Finder or Explorer).

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 Appendix A: Using the Main Menu

Category Options Description

MIDI/Tuning Load MIDI Map Load a saved MIDI CC map from storage.
Save MIDI Map Save a MIDI CC map to storage. By default, MIDI
maps are stored in the Serum 2 Presets > System>
MIDI CC Maps folder.
Saving a MIDI map as default.SerumMIDIMap in the
default folder instructs Serum to load that MIDI map
every time you add an instance of Serum or you load
a preset.
Load Tuning (.tun) Load a tuning file for the current instance of Serum. A
dialog appears allowing you to locate the appropriate
tuning (.tun) file.
See “Using a Tuning File” for more information.
MPE MPE Enabled Enable support for MIDI Polyphonic Expression
(MPE).
When enabled, Serum responds to MPE messages,
allowing for more expressive and nuanced musical
performances using compatible MPE controllers.
Important: In the VST3 version of Serum (not the AU
or AAX versions), when MPE is disabled, Serum will
respond to VST3 Note Expression in cases when the
host DAW supports this feature (this includes hosts
such as Bitwig, Cubase, and Nuendo).
This means that main menu options to map note
expressions to macros remain available and applicable
even when MPE is disabled. However, the MPE Bend
Range option is not available since VST3 pitch note
expression has a fixed range of +/-120 semitones.
MPE: XYZ -> Macro Map the X, Y, and Z axes of an MPE-compatible
1,2,3 controller to Serum macros 1, 2, and 3 respectively.
In this context, the x, y, and z axes represent the three
dimensions of touch-sensitive control associated with
MPE.
Specifically:

• X-axis: Horizontal movement, often used to

control pitch bending.

• Y-axis: Vertical movement, often assigned to

parameters like filter cutoff or modulation depth.

• Z-axis: Pressure or aftertouch, controlling

intensity-related effects like volume or timbre.

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Category Options Description

MPE (cont.) MPE: YZ -> Macro 1,2 Map the X and Y axes of an MPE-compatible
controller to Serum macros 1 and 2 respectively.
MPE: Y -> Mod Wheel Map the Y-axis movement of an MPE controller to the
Modulation Wheel (Mod Wheel) control.
MPE Bend Range: 48 The pitch bend range for MPE controllers, specified as
the number of semitones above or below the original
pitch.
Choose this menu option to display a dialog allowing
you change the current value. You can set any value
from 1 to 96 semitones.
A wider range allows for more expressive pitch
variations and glides across the tonal spectrum.

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Appendix B: Using the Presets Browser
Serum features an advanced presets browser that you can use to quickly access both factory-supplied
presets as well as any presets that you have added.

Click the button to access the presets browser. The browser appears.

Serum Presets Browser

This appendix explains how to use the presets browser to quickly locate the sounds you need and
organize your favorites in a way that best suits your workflow.

Navigating the Folders

The presets browser includes a Folders pane that displays the
presets in a hierarchical structure to help you quickly locate the
right sound.

You can expand and collapse the hierarchy as needed.

Presets Folders

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 Appendix B: Using the Presets Browser

Select a folder in the hierarchy to have the folder contents (presets) appear in the Presets pane.

Presets in the Folder

Loading a Preset
Click an entry in the list to load the corresponding preset.

Most presets load immediately; presets with larger embedded samples, such as multisampled
instruments, display a small green progress bar (directly beneath the preset name) when loading.

Previewing Presets
The browser makes it easy to preview presets. Click the corresponding button to hear the preset
play.

Serum plays an embedded preview clip (MIDI sequence)

if the preset designer specified one. Otherwise, Serum
plays a “fallback” clip to give you a sense of the preset.

You can choose the fallback clip from among three

standard options. Presets Showing Play Buttons

Serum also allows you to auto-preview clips. See “Performing Standard Preset Operations” on page
334 for more information.

Click another play button to preview the corresponding

preset.

Click the button to stop the preview.

Preset Playing

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 Appendix B: Using the Presets Browser

After selecting a preset, press the right arrow key to start the preview and press the left arrow
key to stop the preview. Use the up and down arrow keys to quickly change presets.

While previewing a preset, you can modify any macros that are defined as part of the preset and hear
the effects immediately.

Preset Macros

Searching Presets
You can use the presets browser to help locate the right type of sound by name, category, tag, rating,
and more.

Searching by Name
Perhaps the easiest way to find presets is to search by name. Preset names often contain important
sonic attributes as part of their name. For example, if you’re searching for variations of piano sounds, it’s
often the case that the preset name will include “piano” as part of its name.

Start by choosing a folder in the Folders pane. All searches

in the presets browser are limited to the folder you select.
Search Field
Then type the search term and press the Enter key.

The search results appear. Click the x button to clear the search results.

Searching for Presets

Press Cmd-F (macOS)/Ctrl-F (Windows) to position the cursor in the search field. Note that
this only works when you are already in the presets browser.

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Searching by Categories or Tags

You can also search for presets by categories or tags.

As with any search, start by choosing a folder in the

Folders pane.

Ensure that the CATEGORIES tab is selected.

Searching Using Categories

Then select the appropriate categories in the pane. The

search results appear.

To search by tags, select the TAGS tab.

Then select the appropriate tags in the pane. The search

results appear.

Searching Using Tags

Searching by Ratings
You can search for presets based on the ratings you’ve assigned.

Note: Ratings are user-assigned; presets, by default, have no assigned rating. Ratings allow you to
quickly score presets that you find interesting, allowing you to easily locate them later.

Click the Ratings menu and choose a score from the list
that appears.

The search results appear.

Note that the ratings match exactly. For example, if you

select four stars from the menu, only presets rated with
four stars appear (not four stars or above).

Choose (no rating) using the menu to identify the

presets that you haven’t reviewed and rated. Searching Using Ratings

To show all presets, choose (any rating) in the menu.

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 Appendix B: Using the Presets Browser

Managing Your Presets

The preset browser offers a versatile set of capabilities that allow you to display and edit preset
metadata, rate presets, and perform a range of other operations including renaming, moving, and
deleting your presets.

Displaying and Editing Preset Metadata

You can display the metadata associated with a preset, including the artist, category, description,
comments, date on which the preset was created, and associated tags.

Click a preset in the list. The preset highlights and the metadata appears in the pane on the right.

Preset Metadata

Modify the information, as appropriate. In most fields, click in the field and edit the contents. Two fields
are slightly different: CATEGORY and TAGS. You can read about those below.

Note that you cannot change the DATE field; the preset creation date is managed by the computer
operating system and represents when the preset file was created (or last modified).

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Specifying the Category

To set the preset category, click in the CATEGORY field and
choose an option from the menu that appears.

If you don’t see an appropriate category in the list, choose Custom

to define a new category.

The CATEGORY field becomes editable. Type the new category

name and press the Enter key.

The new category now appears in the list for you to use later, if
needed.

Preset Category

Managing Tags
You can manage the tags associated with a preset.

Click in the field to add a new tag. A menu appears

allowing you to choose from the existing tags.

Preset Tags

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Select a tag or choose New tag to create a new entry. A

dialog appears allowing you to type the name of the tag.

To remove a tag from the preset metadata, click the X

button associated with the tag. The tag is removed.

Rating Presets
Preset Tags
You can rate presets using a one to five-star system and easily search for presets based on their ratings,
allowing you to quickly find presets that capture your interest.

Rating a Preset

Click the corresponding star for the preset you want to rate. To change a rating, click the new star
rating.

To remove a rating, click the first star to select it and then click the same star again to remove the rating.

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 Appendix B: Using the Presets Browser

Performing Standard Preset Operations

You can perform a range of other operations
on presets, including loading random presets,
renaming or moving presets, deleting presets,
and more.

You can also rescan the presets database or

erase and rebuild the database.

Click the button. The presets menu

appears.

Presets Menu

The following describes the operations available:

Category Operation Description

Presets Show Preset in Finder Display the selected preset in the Finder (macOS) or
(macOS) Explorer (Windows).
Show Preset in Folder
(Windows)
Load Random Preset Load a random preset. To load another random
preset, type 7
Hybridize Load a hybrid preset consisting of four randomly-
selected presets. To load another hybrid preset, type
8.
The generated preset name reflects the hybrid mix.

Hybridize Favoring Selected Load a hybrid preset consisting of the currently-

Preset selected preset and three other randomly-selected
presets.
To load another hybrid like this, type 9.

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Category Operation Description

Presets Delete Preset(s) Select one or more presets by clicking a preset or

(cont.) Shift-clicking a set of presets, and choose Delete
Preset(s) from the menu.
You can also type Shift-Backspace to delete the
selected presets.
Important: Serum does not ask for confirmation
before deleting, and there is no way to undo the
deletion from within Serum. Don’t despair. See the
tip below to recover any accidentally deleted presets.
Rename/Move Preset Rename or move a preset.
Select a preset, and choose Rename/Move Preset
from the menu. A macOS or Windows system dialog
appears. Use the dialog to rename or move the
preset, as appropriate.

After returning to Serum, click the button in the

presets browser, and choose Rescan Database from
the menu.
Previews Auto-Play Previews Toggle on to have preset previews play automatically.
After selecting the first preset using the mouse, you
can quickly preview other presets using the up and
down arrow keys.
Preview Fallback Clip Use this option to choose the Serum “fallback” clip to
play when previewing presets.
When previewing presets, Serum plays the author-
designated MIDI preview clip by default (if the preset
author chose to specify a preview clip).

Otherwise, Serum plays the selected fallback clip to

give you a sense of the preset.
Database Rescan Database Rescan the Serum presets database. You can do this
after adding new presets to the Serum 2 Presets
folder.
You can also do this after making other changes to
the database, as described in this section.
Erase and Rebuild Database Do this if rescanning the database (above)
unexpectedly fails to reflect all the presets in the
Serum 2 Presets folder.
Under normal circumstances, you will never likely
need to do this.

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If you accidentally delete one or more presets, Serum moves the preset files to the Trash
(macOS) or Recycle Bin (Windows).

Using macOS, open the Trash, find the preset file, right-click the file, and choose Put Back from
the menu.

Using Windows, open the Recycle Bin, find the preset file, right-click the file, and choose
Restore from the menu.

Return to Serum, click the button in the presets browser, and choose Rescan Database
from the menu. The presets reappear.

You can also perform the most common preset operations by right-clicking a preset and choosing an
option from the menu that appears.

Preset Menu

The following table describes the operations you can perform:

Operation Description

Show in Finder/Folder Display the selected preset in the Finder (macOS) or Explorer (Windows).
Delete Delete the selected preset.
Important: Serum does not ask for confirmation before deleting, and there
is no way to undo the deletion from within Serum. Don’t despair. See the
earlier tip to recover any accidentally deleted presets.
Rename/Move Rename or move the selected preset.
A macOS or Windows system dialog appears. Use the dialog to rename or
move the preset, as appropriate.

After returning to Serum, click the button in the presets browser, and
choose Rescan Database from the menu.

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 Appendix B: Using the Presets Browser

Creating and Exporting a Pack

You can create and export a preset pack from a folder of presets. Right-click a folder and choose Create
and Export Pack in the menu that appears.

Creating and Exporting a Pack

A dialog appears allowing you to specify the pack information.

Preset Pack Dialog

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The following describes the information you can specify:

Field Description

PACK NAME The name of the pack. This is used as the default file name for the preset
pack.
AUTHOR The author name.
Make sure that the button is enabled to prevent users from modifying
the AUTHOR field.
URL The URL of your website.
DESCRIPTION A description of the preset pack.
PACK ARTWORK The artwork for the preset pack. The ideal image size is 436 x 216 pixels.

Click the button. A dialog appears allowing you to locate the image file.
Init disabled Reset disabled oscillators, removing associated parameteres and samples.
oscillators

The following shows an example preset pack:

Sample Preset Pack

Click the button. A dialog appears allowing you to specify the file name and folder.

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The dialog displays details about how the pack was created.

Preset Pack Details

Click the button to show the location of the artist pack. The name of the file is:

<pack-name>.SerumPack

Click the button to dismiss the dialog.

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Appendix D: Editing the Serum Preferences File
Serum stores application preferences in a special file called Serum2Prefs.json. You can find this file
in the following locations:

• (macOS) ~/Library/Preferences/

• (Windows) %APPDATA%\Xfer\Serum 2\ (use Windows Key + R to access)

This file stores the preferences accessible on the Preferences page, the last known path to the Serum
Presets folder, and (optionally) power user options, among other options.

Serum automatically recreates this file if it is missing, so you can reset your preferences to the
factory defaults simply by deleting this file and restarting Serum.

You probably shouldn’t change many of the settings. However, there are a few power user settings that
you might want to explore.

Important: When editing the JSON file, use a text editor application such as TextEdit (macOS) or
Notepad (Windows). Do not use an application that saves the file in any format other than text (the
standard format for JSON files).

For each preference described below, do the following:

1. Edit the Serum2Prefs.json file using a text editor.

2. Make the changes, as described in the corresponding section below.

Very Important: Each line in the configuration file ends with a comma (,). Ensure that you keep the
comma at the end of each line when you edit the file.

3. Save the file.

Changing the Default Artist Name

You can specify the default artist name for the Init preset. This is the name that appears in the ARTIST
field when you initialize a new preset using the main menu.

Locate the following line:

“Default Author”: “ “,

Type the name you want to use between the quotation marks. For example:

“Default Author”: “Wolfgang A. Mozart”,

Any presets made from scratch will now have the name you specified listed as the artist.

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 Appendix D: Editing the Serum Preferences File

Enabling Preset Changes using a MIDI Controller

You can configure Serum to allow you to step through presets using a physical controller (such as a
button on a MIDI keyboard) by mapping the controller’s MIDI CC number to the corresponding preset
selection parameter.

In the Serum preferences file, locate the following line:

“Enable CCForRockers”: 0,

Change the line to the following:

“Enable CCForRockers”: 1,

Next, locate the following lines:

“CCForRocker Preset +”: -1,

“CCForRocker Preset -”: -1,

The first line maps the preset forward arrow (>) to a MIDI CC number; similarly, the second line maps
the preset backward arrow (<) to a MIDI CC number.

Update the -1 values on each line to the appropriate MIDI CC number for your controller (button).

For example, if you would like to assign MIDI CC 21 to the preset forward arrow and MIDI CC 22 to the
preset backward arrow, change the lines to the following:

“CCForRocker Preset +”: 21,

“CCForRocker Preset -”: 22,

For the settings discussed in this section, the value -1 means unassigned.

To remove the MIDI CC assignments that you configured in this section, edit the file and reset
the corresponding values to -1.

A MIDI controller button mapped to a CC typically sends a value of 127 when pressed and
a value of 0 when released. In Serum, a value of 64 or above triggers the action (changes
the preset). Similarly, Serum needs to receive a value below 64 before the action can be
triggered again.

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 Appendix D: Editing the Serum Preferences File

Using Notes to Trigger Preset Changes

Alternatively, you can configure Serum to allow you to step through presets using MIDI notes. The
configuration process is very similar to mapping controller MIDI CC numbers, as described in the
previous section.

In the Serum preferences file, locate the following line:

“Enable CCForRockers”: 0,

The value on this line might already be 1 if you followed the procedure in the previous section. Change
the line to the following:

“Enable CCForRockers”: 2,

Next, locate the following lines:

“CCForRocker Preset +”: -1,

“CCForRocker Preset -”: -1,

Again, the values might be different than -1. As before, the first line maps the preset forward arrow (>)
to a MIDI note number; similarly, the second line maps the preset backward arrow (<) to a MIDI note
number.

Update the values on each line to the appropriate MIDI note number.

Enabling Oscillator Preset Changes using a MIDI Controller

You can similarly configure Serum to allow you to step through oscillator presets using a physical
controller by mapping the controller’s MIDI CC value to the corresponding preset selection parameter.

In the Serum config file, locate the following line:

“Enable CCForRockers”: 0,

Change the line to the following:

“Enable CCForRockers”: 1,

Next, locate the following lines:

“CCForRocker OSC A +”: -1,

“CCForRocker OSC A -”: -1,

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 Appendix D: Editing the Serum Preferences File

The first line maps the OSC A preset forward arrow (>) to a MIDI CC value; similarly, the second line
maps the OSC A preset backward arrow (<) to a MIDI CC value.

Update the -1 values on each line to the appropriate MIDI CC value for your controller (knob).

For example, if you would like to assign MIDI CC 23 to the OSC A preset forward arrow and MIDI CC
24 to the OSC A preset backward arrow, change the lines to the following:

“CCForRocker OSC A +”: 23,

“CCForRocker OSC A -”: 24,

Remember to include the comma (,) at the end of each line. This is important. Also, recall that you can
reset these settings by changing the values back to -1.

Note that OSC B, OSC C, and OSC N (the noise oscillator) have similar settings in the configuration file.
Use the same procedure to assign those to appropriate MIDI CC values for your controllers (knobs).

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Appendix C: Exploring the Serum File Structure
This appendix describes how Serum stores data on your computer drive.

Serum File Structure

The Serum Presets folder contains all the files that Serum reads and writes, except the preferences file.
Serum installs this folder to the following locations by default:

• (macOS) /Library/Audio/Presets/Xfer Records/

• (Windows) /Documents/Xfer/

The following describes some of the more important folders in the file structure:

Folder Description

Arp Banks Contains factory-supplied and user-saved ARP (arpeggiator) banks.

Clip Banks Contains factory-supplied and user-saved CLIP banks.
Multisamples Contains factory-supplied and user-saved multisample instruments.

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 Appendix C: Exploring the Serum File Structure

Folder Description

LFO Shapes Contains LFO shapes (.XferShape files) that are in the same file format
as the shape files used in the LFOTool plug-in. LFO shapes appear in the
following locations:

• The LFO section of Serum

• The waveshaper (in the FX section, when the X-Shaper effect type is
selected and the waveshaper graph is displayed)

• The Remap editor (when WARP mode is set to Remap and the graph is
displayed)
Presets Contains subfolders holding the presets that you see in the presets browser
and menu. These include the factory presets together with any presets you
save.
Samples Contains factory-supplied (tonal and non-tonal) and user-saved samples.
System Contains the four formula files:

• FormulaFactoryMultis

• FormulaFactorySingles

• FormulaUserMultis

• FormulaUserSingles

You can edit any of these text files, but the intent and recommendation is
to edit User files and leave Factory files untouched. See “Using the Formula
Parser” on page 304 for more information about formulas.
The System folder also contains a MIDIccMaps folder, which is where any
MIDI CC maps you create are stored. Finally, the User.dat file holds your
registration information.
Tables Contains subfolders holding the wavetables that you see in Serum. These
include the factory presets along with any wavetables you save. Wavetables
are special Serum-saved WAV files.
You can create your own subfolders in the Tables folder, but Serum does not
scan deeper (no sub-subfolders are scanned).

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Appendix E: Creating Wavetables
This appendix provides additional information about creating wavetables. Refer to “Using the Wavetable
Editor” on page 274 for detailed information about how to create your own wavetables.

What Makes for a Good Wavetable?

Like a good song, creating a good wavetable is about getting that careful balance between consistency
and contrast. Too much consistency or repetition and things won’t feel like much of a journey. Too much
contrast and it’s difficult to draw a connection between random events (like turning the dial on the radio
feels disconnected and hard to comprehend as intentional).

Good wavetables generally have the following basic characteristics:

• Contains many correlated frames

This typically is a sound with a lot of frames, but ones that fluidly work together (think of a pluck
string that decays across many cycles). In general, there might be a lot of individual cycles, but they
all go together well and relate nicely with each other.

Another example would be a synthesizer sample. You want many cycles so it doesn’t feel too
“steppy,” however all the frames should feel as part of a collection (a similarity/sweep across them).

• Contains few frames

Many of the factory presets in popular wavetable synths contain only four or five cycles. This
provides some variety within the table, but not so many waveforms that it feels disconnected or
crazy.

Table Ordering
It typically makes sense to have the frames progress from dull to bright, or vice-versa. You may have a
situation where you want the spectrum to peak somewhere in the middle, but probably not.

You can drag the thumbnails at the bottom of the Waveform Editor to rearrange them. This way, when
you move the WT POS knob, it feels as if you’re traveling in a straight line, instead of in a zig-zag
fashion (spectrally speaking).

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 Appendix E: Creating Wavetables

Interpolation
If you have four frames and automate the WT POS knob, you’ll hear four discrete tones immediately
jumping from one to the next. This is typically undesirable.

In the Wavetable Editor, you can select MORPH > Morph - Crossfade. This is what many wavetable
synths do automatically in every preset wavetable. However, there are times when you might prefer
discrete (non-interpolated) waveforms.

Creating Wavetables from Scratch

There are several ways to create source audio for a wavetable, including the following:

• Drawing

The grid size in lower-right determines snapping. Try different sizes such as 6 or 12 to bring out +7
and +19 harmonics.

• Drawing in FFT bins

Right-click in the bins for a pop-up menu with more options (including random, among others).

• Moving drawings up to FFT bins

Use the curved arrow near the top left and add a new table (using the > button in the lower left).
Then make some adjustments and repeat.

About four frames seem to be a popular number in many other software synthesizers.

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Appendix E: Optimizing Serum
This appendix describes a series of easy-to-adopt approaches to optimizing your sound design results in
Serum.

Exploring CPU Optimization

Serum is designed to optimize audio processing and CPU performance. However, there certain
approaches that you can incorporate to help your sounds achieve the very best performance and
maintain the highest-quality in sound design.

Managing Unison
Unison is a powerful tool for enhancing the depth and richness of a sound by layering multiple voices
slightly detuned or panned, creating a fuller, more powerful tonal presence. However, overuse of unison
can potentially lead to quality and performance issues.

Consider doing the following:

• Keep unison counts low

Using more than three to seven unisons per oscillator is often unnecessary and can potentially
negatively impact efficiency. This is because higher unison counts not only significantly increase
CPU usage, but can also introduce phasing issues, potentially degrading your sound quality.

• Use chorus instead of unison

Instead of stacking unisons to create a thick, chorused sound, use a dedicated FX bus with a
chorus effect. This approach offers two principal advantages. First, by apply the effect once instead
of processing it for every voice, this approach is considerably more CPU friendly.

Second, this provides greater flexibility by allowing easier tweaking and layering of effects without
duplicating processing effort.

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Appendix F: Keyboard Shortcuts
This appendix describes the keyboard shortcuts available in Serum, organized by category.

Presets and Presets Browser

Task macOS Windows

Position the cursor in the search field. Cmd-F Ctrl-F

Note that this only works when you

are already in the presets browser.
Move up a preset ↑ ↑
Move down a preset ↓ ↓
Play preset preview → →
Stop preview ← ←
Select multiple presets Shift-click-presets Shift-click-presets
Delete selected presets Shift-Backspace Shift-Backspace
Save preset using same name Option-click save Alt-click save
without dialog button button

Controls (Knobs and Sliders)

Task macOS Windows

Fine tune setting Shift-drag control Shift-drag control

Reset control Cmd-click control Ctrl-click control

Modules (Oscillators and Filters)

Task macOS Windows

Copy module without modulations Option-drag Alt-drag module

module label label
Copy module with modulations Shift-Option-drag Shift-Alt-drag
module label module label

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 Task macOS Windows

Cycle through filter display modes Option-click Alt-click display

display

The copy module shortcuts also apply to oscillators on the MIXER page.

Sample/Granular/Spectral

Task macOS Windows

Manually add a slice Option-click Alt-click

Remove an existing slice Option-click slice Alt-click slice
Change window amount and skew Option-click and Alt-click and drag
(Granular) drag button button

Audio

Task macOS Windows

Display Renders folder Option-click wave Alt-click wave icon

icon (next to logo) (next to logo)
Copy saved preset to computer Shift-drag wave Shift-drag wave
icon to Finder icon to Explorer

FX

Task macOS Windows

Copy module without modulations Option-drag Alt-drag module

module
Copy module with modulations Shift-Option-drag Shift-Alt-drag
module module
Bypass all FX on a bus Option-click any Alt-click any
bypass button bypass button
Expand/revert the size of the FX rack Option-F Alt-F
and list view

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Matrix

Task macOS Windows

Expand/revert the size of the matrix Option-F Alt-F

view

LFOs

Task macOS Windows

Copy LFO settings Option-drag LFO Alt-drag LFO tab

tab to another to another LFO
LFO tab tab
Add/remove LFO point Double-click Double-click
Draw steps (at grid size) Shift-click draw Shift-click draw
Snap point to grid size Option-drag point Alt-drag point
Move all curve points at once Option-drag any Alt-drag any curve
curve point point
Select multiple points Click-drag on Click-drag on
background background
Select multiple points for relative Cmd-click-drag a Ctrl-click-drag a
movement point point
Set point as loopback position Shift-Cmd-click a Shift-Ctrl-click a
point point
Copy LFO shape to wavetable Option-drag an Alt-drag an LFO
LFO tab to a tab to a wavetable
wavetable

Modulation

Task macOS Windows

Change modulation type (directional Shift-Option-click Shift-Alt-click

or bidirectional) modulated control modulated control

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Clips

Task macOS Windows

Apply changes to parameters to all Option-edit Alt-edit parameter

clips parameter
Scroll piano roll Cmd-Option-drag Ctrl-Alt-drag
background background
Zoom piano roll Shift-Option-drag Shift-Alt-drag
background background
Zoom to marque Shift-Cmd-drag a Shift-Ctrl-drag a
marquee marquee
Scroll piano roll horizontally Shift-mouse wheel Shift-mouse wheel
Zoom piano roll vertically Option-mouse Alt-mouse wheel
wheel
Zoom piano roll horizontally Cmd-mouse Ctrl-mouse wheel
wheel

Clips (Note Movements)

Task macOS Windows

Move selected notes up one ↑ ↑

semitone
Move selected notes down one ↓ ↓
semitone
Move selected notes one position to ← ←
the right
Move selected notes one position to → →
the left
Move selected notes up one octave Shift ↑ Shift ↑
Move selected notes down one Shift ↓ Shift ↓
octave
Shorten selected notes Shift ← Shift ←
Lengthen selected notes Shift → Shift →

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Clips (Note Operations)

Task macOS Windows

Cut selected notes Cmd-X Ctrl-X

Copy selected notes Cmd-C Ctrl-C
Paste selected notes at timeline Cmd-V Ctrl-V
Duplicate selected notes at timeline Cmd-D Ctrl-D
Delete selected notes Backspace Backspace
Chop selected notes Cmd-U Ctrl-U
Conform selected notes to scale Cmd-K Ctrl-K
Apply legato to selected notes Cmd-L Ctrl-L
Mute selected notes 0 (zero) 0 (zero)
Quantize selected notes Cmd-Q Ctrl-Q
Reverse order of selected notes Cmd-R Ctrl-R
Scale time 50% / /
Scale time 200% * *
Double entire clip Cmd-E Ctrl-E
Select all notes Cmd-A Ctrl-A

Wavetable Editor

Task macOS Windows

Move frame to new location Click-drag frame Click-drag frame

Select range of frames Shift-click a frame Shift-click frame
Shift the phase offset to the right Shift-Cmd-click Shift-Ctrl-click
phase offset phase offset

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Additional Credits
The following producers, artists, and sound designers contributed to Serum.

Serum 2 Factory Multisamples

AnSolas Robin Tyndale
Brandon Seliga Rodrigo Montes
Edward “shreddward” Braillif Steve Duda
Matt Aimonetti

Serum 2 Factory Wavetables and Samples

Alice Efe Mr. Bill
Drumsound & Bassline Smith Sharooz
Edward “shreddward” Braillif Splice
ill.gates Steve Duda
Matt Aimonetti Virtual Riot

Serum 2 Factory Presets

7 SKIES Electric Himalaya Oiko
AGENT METHOD Endov Lane Paul Laski
Alice Efe ERB N DUB Scott Diaz
AnSolas Genji Siraisi Skope
Audiotent Gigantor Specimen A
Beatdemon J. Scott G. / Libra Rising Splice
Caster Leo Lauretti Steve Duda
CFA-Sound Level 8 SynthHacker
Chord Shore LP24 Audio Tunecraft
DATABROTH Matt Aimonetti Van Derand
DnBline Smith Mr. Bill Wisteria Motif
Edward “shreddward” Braillif NEST Acoustics

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