Analog modelling (a.k.a virtual analog) software synthesizer
Advanced Gtk+ Sequencer
Your hardcore loop machine
Create, play and print beautiful sheet music
JACK Audio Connection Kit Qt GUI Interface
A fluidsynth Qt GUI Interface
An Audio/MIDI multi-track sequencer
MIDI and Audio Sequencer and Notation Editor
Simple MIDI rhythm box based on ALSA Sequencer
virtual versatile amplification for Jack/Linux
A PipeWire Graph Qt GUI Interface