Audacity - Audacity is a free and open-source audio production software suite that includes a surprising array of editing tools and recording systems.
SoundGrail - SoundGrail Music App designed for pianists, guitarists, and DJs.
Spek - Spek helps to analyse your audio files by showing their spectrogram.
keezy - A colorful soundboard. Play with music.
SoX - Sound eXchange is a command line utility that can convert various formats of computer audio files...
Splice - Music creation, collaboration, and sharing made simple.