WebDrum is a WebAudio drum synthesizer that uses my WebNoise and WebAHDSR projects. Each WebDrum instance can be configured to produce a single drum sound. You can create as many instances as browser performance will allow to produce a varied drum set.

Speaking of browser performance, Chrome currently handles projects with large or complex audio graphs better than Firefox or Safari, so I recommend running WebDrum under Chrome.

Check out the source on Github.