Soldering actually looks good on the bottom. It's just none of the flux has been cleaned off so the board bottoms are ugly as hell at the moment. I'll get it all prettied up and probably reflow everything just to be safe. At the least though, for what cost me about $700+ shipping (trade was worth a lot more but that's what I paid for what I traded), I don't mind spending a little time to fiddle with things. Edit: Looking over the BOM for the amp boards here again https://docs.google.com/spreadsheets/d/1tQvwqsARXGge6Tw6edqicCDti6Mite2F24T5YddyEEc/edit?pli=1#gid=0 It has the 250 ohm R for the IXYS parts build. But I can use 180 ohm R in an IXYS current source 500v build as long as the onboard sinks dissipate the heat? Otherwise, it seems most of the parts I thought were missing have the A designation so should be left alone right? The mentioned jumper in the upper right is also marked A instead of I. So it should also be left alone? I also needed to ask again about the local vs. global feedback jumper. What's the standard everyone uses in their builds?