Jokosher - Jokosher is a simple and powerful multi-track studio.
LMMS - Make music with a free, cross-platform tool
Fission - Edit audio in minutes, not hours.
GarageBand - GarageBand is a fully equipped music creation studio for Mac
Audacity - Audacity is a free and open-source audio production software suite that includes a surprising array of editing tools and recording systems.
Ableton Live - Ableton makes Push and Live, hardware and software for music production, creation and performance. Ableton´s products are made to inspire creative music-making.