The SND files (background music) were developed with the MusyX SDK for Nintendo GameCube, and are sequenced MIDI file containers. There's currently no way to play them.
The DSP variant you speak of is simply the sound samples used for the sequence files, which are indeed GameCube ADPCM (DSP).
@manako - I've already made a 'file splitter' for these SND files, ages ago. Of course there's no point, as in_cube/vgmstream doesn't support sequenced formats.
The "sequenced" stuff is nonsense for RE1 NGC, it's simple dsp, here's the file he uploaded with a genh header. Maybe it was created with the MusyX SDK, but as you can see, there's no sequence stuff involved, only some container files. The only thing that a midi-like file could do here is maybe changing the track in the container, for me it is streamed, not sequenced.
Could it be that you're confusing RE1 with RE Zero?
No I am not confusing the two - in fact, they both use the MusyX format; Zero's files are seperated whereas Bio1's MusyX files are archived in the SND files. And for the record, I am reffering to the GameCube versions, not Wii.
Perhaps some files are really DSP files masked with the SND extension, but I assure you, both GameCube titles use sequences for background music. For even further proof, i've used Bio-Remake's music in Zero using some special tools I made - simply to prove to myself that they both use the same sequenced format.
Ever listened to disc four of the biohazard SOUND CHRONICLE BEST TRACK BOX? Then you'll know how much they butchered the OST release for the remake – they cut half of the game's compositions and raised the high frequencies of all tracks so much that it sounds like some cheap hissy retro synth (comp. "Tyrant-2"). And they turned the volume for some of the very quiet tracks up too much, resulting in some very annoying peak problems (comp. "Concrete Bound"). This rip here uses the original GC sound driver and includes everything, from unused compositions to trailer and development movie extracts (116 tracks in total).
Oh yeah, and please show some gratitude to my dear assistant, Bob. Without him and his suspenseful around-liery, this would not have been possible.
Side-note about the unused tracks: • "x9-30" is a remix of a track from the original game (played in the gallery after the puzzle has been solved and the wall disappears) • "x9-31" is a remix of a track from the original game (played when Jill meets Barry in the underground cave) • "x9-32" is a remix of a track from the original game (played in the underground cave) • "x9-33" and "x9-34" are two versions of an unused cutscene track • "x9-35" and "x9-36" are probably concept compositions for the "Result" screen