Modular music composer

 Buzztrax aims to be a music studio that allows one to compose songs using
 only a computer with a soundcard. If you’ve used tracker programs like
 FastTracker, Impulse Tracker, or the original AMIGA SoundTracker, that will
 give you an idea of how one can sequence music in Buzztrax. The Buzztrax
 editor uses a similar concept, where a song consists of a sequence with
 tracks and in each track one uses patterns with events (musical notes and
 control changes). In contrast to other Tracker programs, tracks are not
 simply sample players: a user can make a song using an arrangement of virtual
 audio plugins that are linked together to create different effects. Each of
 these machines can be controlled realtime or via patterns in the sequencer.