PlayerPRO is a complete music editing program (SoundTracker).
Uses XI, Quicktime or SoundFonts. Currently runs on MacOS and OSX; playback engines also available for Windows and BeOS. Upcoming version 6 will support ALSA (Linux).
PlayerPRO can load and play the following music (and sound) formats:
MOD, S3M, MIDI, MTM, MADH, MADG, MADI, MADK, OKTA, MINS, XI, PP, Clip File, MED, 669, IT, ULT, XM System 7 sound, WAV, AIFF, AIFC, SoundDesignerII, MPEG, MP3, MuLaw, ALaw, AVI, DVC, Quicktime Movies, MAC3, MAC6, IMA4, MPEG layer I, II and III (requires QT 4.0), PAT (GUS), QDesign, RAW Data.
This version is open-sourced and in the public domain.