I see a few requests for help about electronic circuits. That's fine but this probably is not the best place to get an answer! I started this section more to answer questions about the Soundplane theory and help people making a homebrew version. I'm not that skilled at electronic design myself, in general.
Dangerous Prototypes is also a good site with lots of open-hardware and open-source projects. It's basically Hack-a-Day for electronics design.