The unit arrived today, here's what was wrong.
1. TR605 wasn't completely soldered to the board. I sucked off the solder on the emitter and low and behold there is no lead, it wasn't all the way through.
2. The reason for the strange base voltage on tr602. C601 is the filter cap for that transistors base, instead of having a 47uf cap installed it had 4.7uf. Once the cap was swapped and the transistor resoldered it came out of protection. I soldered tr605 before I caught the wrong cap and it was still funky.
3. The reason for the hum- I disconnected the amps from the signal path and fired it up, no more hum. I checked the voltages and scoped the power going to the pre, where I was supposed to have 30 and -30 I had 36 and 38 and the voltage had noise. I pulled and tested TR01 and 02 and they passed. I noticed they had been removed previously, only problem is that they were swapped. Swapped em back to where they belong and the hum is now gone. Bias and DC offset is spot on and it's quiet as a mouse.
That's all she wrote. It's a really nice, clean unit. I offered it back to 147JK but he doesn't want it back, too bad, cause it sounds really good.
Never too late to change your mind ya know
Maybe this will convince him.
http://www.youtube.com/watch?v=VfQOVLAovys
