Browser Synth
Acid 303
A web-native Roland TB-303 inspired monosynth, built from the feel of the original `js303` project and redesigned with a playable three-octave keyboard.
Oscilloscope
TB-303 Style Bass Line
Audio sleeping
PC octave: 3
Performance
3-octave keyboard
Play on-screen, or use A to J with the black-note keys above them.
Use Z and X to shift the active PC octave.
Showcase
Demo performance
Load the built-in acid line, play it back, or export the pattern as JSON for sharing.
Import edited JSON back into the app to swap in a new demo without changing the code.
Demo ready
During demo playback, starting live keyboard play, loading a different demo, and importing new demo JSON are disabled.