nicetas_c said sound chips. I don't think it's possible to expand upon what the CPU and SPC700 already provide (though you can do pretty advanced stuff like streaming audio if you know how).
N106 is like 8 FDS channels without the FM stuff and shorter wavetables.
That, and depending on how many channels you want to use (8 or 4 or 2), the lower the number of wave-table channels the longer the wave-tables in channel. This is purely from my understanding, though, so I could be wrong.
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Someone set up us the bomb!
Something makes me think that there was a sound chip or two available....
I think there might have been, but I think that may have been for some streaming audio and not necessarily for music. See Jikkyo Oshaberi Parodius (am I spelling the romanji right?) for said example.
I know for definite there was a 3D chip. See Starfox and Vortex.
So yes, there were add-on chips for the SNES, but not necessarily for music from my understanding. I would think that the sample-based system of music would have been sufficient enough, personally.
Although it isn't backward compatible with the 2A03, it can simulate it by using samples. See Donkey Kong Country's intro music. I think it did an ok job of simulating it, but not perfect, as the SNES has something like an anti-aliasing filter.
BTW, sorry to get off topic there... ^_^'
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Someone set up us the bomb!
There were sound chips, just not used for music, even though compatible. One, I beleive, was like a minichip version of the 2a03 internal chip in the NES.
