GUI to work with abc notation
JACK Audio Connection Kit Qt GUI Interface
Free media player with support for Youtube
An Audio/MIDI multi-track sequencer
Multiplatform GUI of MP3Gain which adjusts volume of MP3 files
Audio converter and CD ripper for various formats
MuldeR's OpenSource Projects
A fluidsynth Qt GUI Interface
An old-school polyphonic sampler
An old-school polyphonic synthesizer
Multiplatform MIDI File Player for Linux, Windows, and macOS
An old-school drum-kit sampler
The X Jack Video Monitor
A MIDI Network Gateway via UDP/IP Multicast
An old-school polyphonic additive synthesizer
MIDI Metronome using the ALSA Sequencer
Linux Studio Plugins Project
A LinuxSampler Qt GUI Interface
MIDI monitor for Linux
A MIDI Remote Controller via UDP/IP Multicast