My 4B-ST runs Hot

Just got a response from Bryston. They want me to see if I can duplicate the problem after I switch my speakers around. Guess they want to rule out a bad speaker or cable. I'm going to try it again, but I've moved my system to different rooms in my house often enough to have switched the speakers around several times. This heat thing has pretty much been a feature of the amp since I got it. Oh well, I'll keep everyone posted on what happens.

Guys, I had this problem and here is the fix which I got from Bryston. I had the same problem with my 3B getting hottor on one side more than the other. You have is Biasing problem. Here is the procedure to fix it.

The bias procedure for the 3B amplifiers is as follows:
Remove the top panel of the amplifier, and locate the 2 pairs of test points on the PCB. They will be on the left side of the main board for each channel, between the large 5W power resistors.(The newest amplifiers have them at the top left corner of the

board). Using a millivolt meter, measure the Voltage between

each of the pairs of test points. It should read between 10 and 15millivolts on each pair, or a TOTAL of 20-3OmV. (One may be higher than the other, this is not important, only the total). If it is higher, or lower, than 20-3OmV total, the bias may be adjusted by the rotary potentiometer control in the center of the board,(clockwise is to increase the reading). When the reading is within

the correct range, with the amplifier idling and no input connected, temporarily place the top panel on the amp, and leave it for 15-20minutes. Repeat the reading, and adjust if necessary. The bias is properly set when the reading stays within the correct range for 2successive readings. Then re-install the top screws, and the amp is now set. (Note: on older amplifiers, the test points may not be present. The readings may be taken directly across the large 5Wresistors in that case, and only one resistor need be used for the test. In this case, the reading is only the 10-15mV reading of one).
Good luck
Mohamed

Well, switching speakers or cables around did nothing to diminish the heat problem. The unit is going back to Bryston tomorrow. Hopefully the excessive heat did not damage the internal components.