The music in the SNES game Super Mario World uses heavily-compressed samples to fit within the constraints of early 1990s' hardware. Fans exploring the Nintendo leak were able to figure out the sample libraries that composer Koji Kondo used and "restore" the sountrack as it sounded on the hardware he presumably created it with.
A video game music researcher who goes by The Brickster told Polygon over Discord that he first found the names of the original sound samples in the Nintendo gigaleak. After that, he and a team of friends figured out which instruments were used to create the soundtrack, using the file names as well as research about which instruments the composer, Koji Kondo, used at the time.
"For example, one sound was called 'fantasy' in the source files," The Brickster said. "Knowing what I knew of Kondo's setup during the time of Mario World, I deduced this must mean the 'Fantasia' patch from the Roland D-550, a synth he owned at the time."
It's magical to hear it, like stepping out of an audio flatland into three dimensions.
But it's also a bit weird: the music's gone from something that sounded rich in the context of a game console to something that sounds simple, even minimalistic, in the context of production music.
Here' s something to consider. Just as old pixel art was often drawn with blurry CRT displays and shadowy gamma curves in mind…
…old game music was intentionally produced for (and mastered using) the target systems. Compression artifacts, downconverting samples and the indefinite 'color' of old chips, all introduce new qualities to sounds that were anticipated and expected.
A crude but simple illustration: if you're old enough to have been in arcades in 1985, the theme from Sega's Hang On likely sounds tinnier than you remember. That's because the speakers in the cabinets were heavily baffled, softening the music and giving it a bass boost. It was likely produced with those speakers in mind. Running the Hang On Theme's data bit by bit from an emulator to a FLAC file doesn't recover lost perfection, it finds a headache.
The extent to which Super Mario World's instrumentation was simply squashed post-production to fit on this little fella, or intentionally designed for it, is maybe a question for Kondo?