Sample-free General MIDI player and renderer. Every voice is generated algorithmically — no SoundFont, no sample library, no FluidSynth. Expect a chiptune / analog-synth aesthetic.

cargo install rumpl

Or from a local checkout:

cargo install --path .

rumpl play   file.mid               # real-time playback
rumpl render file.mid out.wav       # offline render to 44.1 kHz / 16-bit stereo WAV

Flags:

• --gain <f32> — master gain (default 0.8)
• --sample-rate <u32> — render sample rate (default 44100)
• --tail <f32> — render seconds of release tail after last note-off (default 3.0)

• midly parses the SMF; events are merged across tracks and stamped with absolute sample indices via the tempo map.
• A 64-voice synth maps each MIDI program to a static Patch (oscillator stack, ADSR, filter, LFO). Channel 10 uses a separate per-key drum patch table.
• Output goes to cpal for play or hound for render.