TU-3Chromatic Tuner

TU-3

The Gold Standard in Stage Tuning

The TU-3—the world’s best-selling stage tuner—unites trusted BOSS tuning technology with our iconic compact pedal format. Top performers everywhere rely on this robust stomp for fast and flawless tuning night after night, thanks to its high-visibility meter, simple operation, and road-tested durability. The versatile TU-3 also includes a mute function, tone-saving buffer, and power distribution capabilities, making it an essential utility tool for every player.

TU-3

Features

  • Sharp 21-segment LED meter with brightness control
  • High Brightness mode enhances meter visibility when playing outdoors
  • Accurate to +/- one cent
  • Accu-Pitch Sign function provides visual verification when tuning is complete
  • Chromatic mode for tuning to any pitch
  • Guitar and Bass modes for tuning by string number, with support for 7-string guitars and 5- and 6-string basses
  • Flat tuning options support down tuning up to six semitones below standard pitch (Guitar mode) and three semitones below (Bass mode)
  • The output automatically mutes when the tuner is engaged, allowing for silent tuning on stage
  • DC output jack for distributing power to other pedals (requires optional PSA-series adaptor and PCS-20A parallel cable)
  • BOSS five-year warranty
TU-3

Leading the Industry for Nearly Three Decades

In 1998, BOSS introduced the TU-2, the world’s first pedal-based chromatic tuner. This game-changing product was an instant smash, making stage tuning easier and more convenient than ever before. The TU-3 followed in 2009, building on its popular predecessor with increased tuning precision, an enhanced LED meter, and expanded modes. Regularly seen on stages across the globe, TU pedals continue to be the go-to tuners for everyone from local players to famous touring pros.

TU-3

Precision Tuning Made Easy

The TU-3’s sharp, 21-segment LED meter takes the guesswork out of tuning, offering both Cent and strobe-style Stream options for your preference. Our innovative Accu-Pitch Sign function speeds operation on stage by displaying a bright streaming indicator when you’ve reached your target. The default Chromatic mode automatically detects any incoming pitch, while selectable Guitar and Bass modes provide quick, string-based tuning with support for extended-range instruments and down tunings.

TU-3

Pitch-Perfect Performance

The TU-3 packs a ton of practical features into its compact size. Engaging the pedal activates a mute function, allowing you to tune silently and keep your rig quiet during instrument changes and set breaks. High Brightness mode cuts through glare for improved meter visibility on sunlit outdoor stages. And when powering the TU-3 with an optional PSA-series adapter, you can use a PCS-20A parallel cable to distribute power to other pedals on your board.

Specifications
Tuning Range
C0 (16.35 Hz)--C8 (4,186 Hz)
Reference Pitch
A4 = 436--445 Hz (1 Hz step)
Tuning Accuracy
+/- 1 cent
Modes
Chromatic
Chromatic flat x2
Guitar
Guitar flat x2
Bass
Bass flat x3
Display mode
Cent mode
Stream mode
Power Supply
Carbon-zinc battery (9V, 6F22) or Alkaline battery (9V, 6LR61)
AC adaptor (sold separately)
Bypass
Buffered bypass
Controls
Pedal switch
MODE button
STREAM/CENT button
Nominal Input Level
-20 dBu
Input Impedance
1 M ohm
Nominal Output Level
-20 dBu
Output Impedance
1 k ohm
Recommended Load Impedance
10 k ohms or greater
Indicator
CHECK indicator (Serves also as battery check indicator)
Connectors
INPUT jack
OUTPUT jack
BYPASS jack
DC IN jack
DC OUT jack
Current Draw
20 mA (DC 9 V)
80 mA (DC 9 V, when High Brightness mode is on)
Expected battery life under continuous use
Carbon: Approx. 5 hours
Alkaline: Approx. 21 hours
*These figures will vary depending on the actual conditions of use.
Accessories
Leaflet ("USING THE UNIT SAFELY," "IMPORTANT NOTE," and "Information")
Carbon-zinc battery (9V, 6F22)
Options (sold separately)
AC adaptor: PSA series
Parallel DC cord: PCS-20A(DC Plug x8)
Size and Weight
Width
73 mm
2-7/8 inches
Depth
129 mm
5-1/8 inches
Height
59 mm
2-3/8 inches
Weight (including battery)
390 g
14 oz
* 0 dBu = 0.775 Vrms
*The specifications are subject to change without notice.

Video Library

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Why Buffers are Important for Great Tone

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Every BOSS pedal includes a buffer, an essential tool for keeping your guitar sounding great. Learn more about this tone-saving feature.Read more…

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Support

If you have questions about operating your BOSS product, please check our Knowledge Base for answers to the most common questions.
You can also contact our Product Support department by phone or email.
In addition, we have a library of Owner’s Manuals and Support Documents that you can download and reference.

Owner’s Manuals