Join Date: Oct 2004
Location: Victorville, CA
I'm a total newb but I am wondering if you have taken a voltage reading across the filter caps. (Yes, the big main caps in the power supply.)
That is the first place I would try. Measure the DC voltage across the terminals of each cap. Then measure for AC across them. If any of them read differently than the others or if you see much AC at all, the caps are probably bad. I have fixed a few power amps by simply changing out bad filter caps. They certainly can cause hum in the transformer in my experience.
Post the voltages you read and then maybe someone who actually likes Krells might be able to help you further.