Tracery : A story-grammar generation library for javascript. Write grammar objects, get generative stories.
jsmad : jsmad is a pure javascript MP3 decoder, based on libmad, with an ID3 decoder written from scratch.
meSing.js : meSing.js is a JavaScript singing synthesis library that uses the Web Audio API's DSP capabilities in conjunction with the meSpeak.js speech synthesis...
Wave.js : Audio visualizer library for javascript. Create dynamic animations that react to an audio file or audio stream.
Band.js : An interface for the Web Audio API that supports rhythms, multiple instruments, repeating sections, and complex time signatures.
This is a javascript library (with frontend) for sound effect generation.