The sound chip used in both the sfc and the snes is the SPC700, with no differences in audio quality. However, there have been MSU1 game hacks where pre-recorded cd audio ( usually a remix of the game's audio) can be streamed through the spc700 soundchip and replace the regular soundtrack. Those hacks can usually be played w/ a sd2snes or everdrive on your console ( along with emulation).
