MIDI/Audio multi-track sequencer application

 Qtractor is a MIDI/Audio multi-track sequencer application written
 in C++ around the Qt4 toolkit using Qt Designer.
 .
 The Jack Audio Connection Kit (JACK) for audio, and the Advanced Linux
 Sound Architecture (ALSA) for MIDI, are the main infrastructures to
 evolve as a fairly-featured Linux Desktop Audio Workstation GUI, especially
 dedicated to the personal home-studio.