There have been prior experiments to synthesize audio with javascript, and feed it into the <audio> tag via data-uri.<p><a href="http://ajaxian.com/archives/generating-and-playing-sound-in-javascript" rel="nofollow">http://ajaxian.com/archives/generating-and-playing-sound-in-...</a><p>But I've never seen it done realtime like this! Very cool.