SoundManager 2 : Using HTML5 and Flash, SoundManager 2 provides reliable cross-platform audio under a single JavaScript API.
howler.js : howler.js is an audio library for the modern web. It defaults to Web Audio API and falls back to HTML5 Audio.
meSpeak.js : meSpeak.js (modulary enhanced speak.js) is a 100% client-side JavaScript text-to-speech library
Wave.js : Audio visualizer library for javascript. Create dynamic animations that react to an audio file or audio stream.
jsfx : This is a javascript library (with frontend) for sound effect generation.
howler.js is an audio library for the modern web. It defaults to Web Audio API and falls back to HTML5 Audio. This makes working with audio in JavaScript easy and reliable across all platforms.