Just came back here to say that it was this video that got me into tracker music, midi transcriptions, and the demoscene. Seriously love this song, thanks
This format may be the dream of any game music sequencer. In fact, correct me if I'm wrong.. many Gamecube musics are done by multichannel sequencing instead of full loop audio, isn't it?
Yes, they're BMS files. There's a video on RU-vid called "Gamecube BMS audio player" that shows it in action. Not sure if there's any BMS player available to download, though.