beeper: toy subtractive synth

A toy subtractive synth. Only 16 controls, surprisingly capable.

Play with the controls to learn a little of sound design by practice. Most beginner synths greet you with 40–50 knobs; beeper has 16, picked to give a wide range of sounds without the clutter.

Quick start

• 1–9, 0, -, = — pick one of 12 sound presets (each comes with its own demo loop)
• Up/Down — select a control, Left/Right — adjust it
• Space — toggle checkboxes (Sustain, Solo), s — solo, m — mute all
• Any preset works with any loop — that's 144 combinations before you've touched a single slider. Tweak Cutoff, Glide, or Drive on a running loop and see what happens.

beeper is written in C (~1,800 lines) for an ESP32 embedded project. This web version is the same code compiled to WASM. Two instrument tracks plus a simple drum track. No MIDI, no saving, no chord level polyphony: it is just a music toy with some potential for learning.

Clone/fork for your game sound, or your own sequencer/DAW/whatever. MIT license.

https://github.com/valdanylchuk/beeper

Have fun!