VGMRips

This site provides game music rips from many video game systems, both arcade and home.

The VGM format is interesting because it captures raw commands as sent to the music chip [1] It's kind of like .nsf or .sid, but supporting a huge array of sound chips based on different tech - simple square wave, FM synthesis or PCM sampling.

[1] https://vgmrips.net/wiki/VGM_Specification