[Jamie]

Tubes check good, and I swapped in a totally different set too...just to be sure. I rebuilt all of the bakelites, replaced all the other caps and I think I checked all the resistors. I've gone through all the wiring, everything looks kosher. The hum is not tunable. It is constant. There is one large resistor that's drifted pretty high, but I don't have a replacement that's high enough wattage ( I think it was no 47, but I can't recall for sure and I'm not at my bench now). Voltage on all the tubes seems to be acceptable levels.. maybe a little high, but nothing way out of whack.