If you look hard enough, you can find audiophile geeks out there that would be happy to have a project like upgrading a stock system. I had a friend in Austin that owned an a/v repair store, and he would routinely take Alpines/Kenwoods/etc and upgrade the internal components for better noise control or add balanced outputs, whatever.
It was a welcome change for him, compared to the same old amp repairs every day.
If I remember correctly, a common audiophile upgrade is to replace electrolytic capacitors in the audio path with polyester or Tantalum caps, since poly won't smear the signal as much as other types will.. search the web. There's info out there.
-=RB
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