Yoshimi is a software audio synthesizer, originally forked from ZynAddSubFX.
LMMS
Let’s make music
with a free, cross-platform tool for your computer.
Drumkv1
drumkv1 is an old-school all-digital drum-kit sampler synthesizer with stereo fx.
Patroneo
An easy to use, pattern based midi sequencer, a program that sends digital “notes” to software instruments such as synthesizers and samplers.
NON
Non is it resultaat fan it winsk fan ien man om in folsleine fergoeding te bouwen fan in foltôge-software Digital Audio-wurkstasjon op GNU / Linux dat echt wurket-op tagonklike hardware.
Rosegarden
Rosegarden is a music composition and editing environment based around a MIDI sequencer that features a rich understanding of music notation and includes basic support for digital audio.
Muse Score
Create, play and print beautiful sheet music
Luppp
Luppp is in ark foar muzyk oan it wurk, bedoeld foar live gebrûk. De fokus is op echte tiidferwurking en in rappe en yntuïtyf workflow.
padthv1
padthv1 is an old-school polyphonic additive synthesizer with stereo fx.
Cecilia
Cecilia is an audio signal processing environment aimed at sound designers. Cecilia mangles sound in ways unheard of. Cecilia lets you create your own GUI using a simple syntax. Cecilia comes with many original built-in modules and presets for sound effects and synthesis.