Demos / Web Audio synth
A keyboard you can play.
A monophonic oscillator with an envelope and a low-pass filter, all
built from AudioContext nodes. iPad has a real speaker;
plug in headphones for the full effect.
Tap a key to start the audio context
Waveform
Cutoff
The graph
For every key press we spawn a fresh oscillator, route it through a
biquad low-pass filter, then a per-note gain that does the
attack/decay/sustain/release envelope, then the master gain into
ctx.destination.
Mobile Safari won't let an AudioContext start without a
user gesture; the first tap on a key is what unsuspends it.