Since I've received a few PM's on this thread I thought I would post a PDF of the mod I performed on the Palomino for anyone who is interested. Even though a single 25 watt aluminum resistor can more than handle the cathode current of this amp, I went with two double valued units in parallel to increase the contact surface area of the resistance at the chassis metal bottom. I did this to improve heat rejection into the cabinet and away from the chassis internal area. It seems to work very well, as it dropped the temp around the controls and at the board significantly. Increasing the net value of the cathode resistors (as mentioned in the attachment) would probably help even more and extend the life of the tubes as well. The 25 watt resistors can be found on Mouser.com by searching the phrase "aluminum resistor" currently page 645 of their catalog:
http://www.mouser.com/Search/Product...EYbTFjJwKbM%3d
Barry
http://www.mouser.com/Search/Product...EYbTFjJwKbM%3d
Barry
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