* [SoundManager2](http://www.schillmania.com/projects/soundmanager2/) JS api, but uses flash for playing audio, providing spectrum data. has experimental HTML5 branch.
* [SoundJS](https://github.com/TooTallNate/SoundJS) A JavaScript sound loading, playing and layering library  designed for browser-based games to have a multi-layering sound API.
* [audiolib.js](https://github.com/jussi-kalliokoski/audiolib.js) normalizing library between the two audio APIs 
  * has effects, synthesis, envelopes, recording and exporting
* [XAudioJS](https://github.com/grantgalitz/XAudioJS) shim for basic audio handling between the two apis
  * grant wrote [an HTML5 emulator of GameBoyColor to HTML5](https://github.com/grantgalitz/GameBoy-Online) and uses the audio apis there
* [dynamicaudio.js](https://github.com/bfirsh/dynamicaudio.js/) Moz Audio Data API polyfill via flash.
  * also an author of [a nintendo emulator](http://benfirshman.com/projects/jsnes/)
* [audionode.js](https://github.com/corbanbrook/audionode.js) polyfill of Web Audio API using the moz audio data api.
  * done back in july so it may not still be compatible..
  * corban is one of the guys on the mozilla audio/webgl demo team
* [audiodata](https://github.com/notmasteryet/audiodata) abstraction layer for audio data api
* [beatdetektor.js](https://beatdetektor.svn.sourceforge.net/svnroot/beatdetektor/trunk/core/js/beatdetektor.js) detects beats... and uses...
* [dsp.js](https://github.com/corbanbrook/dsp.js) for its DSP action, and can work with both APIs
* [Audiolet](https://github.com/oampo/audiolet) library for synthesis and composition with support for both APIs
* [music.js](https://github.com/GregJ/music.js) generates notes, intervals, chords, and scales across both APIs
* [jsmad](https://github.com/nddrylliog/jsmad) mp3 decoder, or rather:
  * MPEG-1 demuxer
  * MPEG-1 Layer III decoder
  * ID3v2 reader
  * Will eventually be split into io.js, mpeg1.js, mp3.js and id3v2.js
* [Buzz](http://buzz.jaysalvat.com/) A Javascript HTML5 Audio library
* [javascript-audio-fx](https://github.com/jakesgordon/javascript-audio-fx/)
* [Alac.js](https://github.com/ofmlabs/alac.js/) - An Apple Lossless decoder in the browser
* [audia](https://github.com/richtaur/audia)
* [howler.js](https://github.com/goldfire/howler.js) defaults to Web Audio and falls back to HTML5 Audio
* [ion.Sound](https://github.com/IonDen/ion.sound) Small plugin for playing sounds on events

## Other

* [JPC2000](http://jpc.heroku.com/index.html) - Chrome only