It runs in the browser, it doesn’t use Flash and it makes a whole lot of bleepy noises.
SamplePlayer, created by electronic musician and web programmer Almer Thie, is a musical keyboard, sequencer and signal processor embedded in an web app. To power SamplePlayer, Thie utilizes the experimental Audio API in Firefox — he’s running a special build of Firefox with support for the Audio API rolled into it, so most of us will have to settle for the video above.
All the sliders are jQuery creations. Plus — those duck noises? Awesome.
If you’d like to experiment with Firefox and audio, have a look at the Mozilla developer documents using audio and video in Firefox.