In fact you can find a topic on NesDev which explain that is not something easy to do, maybe even not possible because of the SNES sound architecture and the SPC format itself.

I guess the one you were speaking about (only playing one SPC file) is this one :
http://jiggawatt.org/badc0de/spcplayer.htm

Ello ello,

I've searched far and wide, and can't seem to find technology that lets you put multiple spc's on one rom for soundtrack/album collection play. VMG_PLAY by deadfish shitware allows this on genesis, and the classic .nsf allows this on NES.
Found this thread: http://chipmusic.org/forums/topic/4304/ … r-for-nes/ with SPC player for SNES, but it allows only one spc per smc/rom.
I've also stumbled upon the .sp2 file format here:  http://forums.nesdev.com/viewtopic.php?t=8558 but I can't get it to work... stated that it needs a player made for the format since it needs unpacking inherently.
http://battleofthebits.org/arena/Battle/2087/Comments/ This page on BotB (the second last comment) shows B00daw saying an sp2 player is in the works... but maybe nothing came out of this? I've messaged kevtris on youtube, but no answer so far.

This is the closest I've come so far.

I know it could be because the separate tracks communicate differently with the CPU, but I was wondering if the gurus here might have any more info for me.

Thanks
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