Audacity
Audacity records and edits sounds with aplomb, with tons of new features constantly being added.
Audio
eqMac
Adjust the sound coming from your Mac’s headphones or speaker.
LMMS
Create melodies and beats, synthesizing and mixing sounds, arranging samples and much more. The playback with a typing or MIDI keyboard. Bundled with ready-to-use content.
RGB MusicLab
Ever wonder what a musical Mona Lisa would sound like? RGB MusicLab takes the pixels in a painting, judges their colours and brightness, then interprets them to create music. Don’t like what you hear? There are many options to adjust your final composition.
Riffworks T4
Guitar recording and online collaboration program includes looped recording, automatic track creation, InstantDrummer, effects, song posting, online collaboration, and a tutorial in 14 languages. You can record songs online with friends for free.
Shazam
Click on Shazam to listen to any music playing on your computer, or within earshot. It will give you the name and artist.
Tomahawk
Open source music player without the iTunes bloat allows you to gather all your music sources and downloads in one place. Create playlists, invite friends, listen to radio stations.