amp is hot on one side cold on the other

I have a forte 1a amp, the last time I plugged it in I noticed that the left side of it was running hot after about twenty minutes or so yet the right side was cool, also when I shut the amp off while still playing the left side stops immediately while the right continues to play for a while, thanks for any help, mike

Showing 1 response by sean

I used to have a Forte 1A and still have several other Forte' amps. Since they are all biased relatively heavy into Class A, they will run measurably warmer than most other amps. Your amp, while only being 40 wpc, is pure Class A and should normally run warm. Both of the things that you mention imply that the two channels are running "out of sync" with each other. Bias is obviously not the same on both sides and some of the filter caps for that channel may have also been weakened for one reason or another. I would highly recommend contacting Jon Solderberg at vintage Amp Repair as to what he would suggest. Jon used to work for Threshold and has a website at and can be contacted through an email link there. He is sometimes a little slow to respond to email, so be patient. Try to give him as much info as to the specifics of your situation as that can only help him assess what the best plan of attack is. Good luck and hope you have a spare amp : ) Sean >