This is most likely because the SNES's audio was entire ADPCM based. The CPS1 was basically doing MIDI, while all audio on the SNES was done with samples, and s

This is most likely because the SNES's audio was entire ADPCM based. The CPS1 was basically doing MIDI, while all audio on the SNES was done with samples, and so the samples could be made to sound more realistic than typical MIDI.