VAST G1-J5 — Free Browser Synthesizer

VAST G1-J5 is a free, in-browser polyphonic subtractive synthesizer built on the Web Audio API — no install and no signup. It runs entirely in your browser and requires JavaScript to be enabled.

What it does

8-voice polyphonic synth: dual oscillators, sub oscillator, noise, and unison.
Moog-style 4-pole ladder filter with resonance and drive.
Two ADSR envelopes and an LFO routable to cutoff, pitch, amp, or pulse width.
FX chain: distortion, wah, phaser, delay, and reverb.
Arpeggiator, 16-step note sequencer, 8-track drum machine, and an 8-slot sampler.
Record and edit samples from your microphone, build song-chain arrangements, and apply live DJ FX.
Export to WAV/MP3 and save/load songs as portable JSON files. Play with the on-screen keyboard, your computer keyboard, or Web MIDI.

VAST G1-J5 is free and open source — the full source code is on GitHub.

Please enable JavaScript to use the synthesizer.