This is kinda old but i just came across it and thought I'd post this on here. Pretty cool stuff...
http://www.1up.com/news/track-composer-contra-nes
If you scroll down there's some other interviews as well.
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Tulsa, OK
thanks for sharing this 
it was pretty cool. was he talking about working with 3 channels?
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Neo Jersey
yea he mentions the limitations of the hardware and some of the tricks they used like echos to get a fuller sound.