Hi Terry - Thanks for your info on my schematics question. I recently bought a tube tester, and after checking all my tubes I'll update my thread on fixing those old MC30's.
Meantime, I have a question about the mint MC30 pair I bought from you and Tom. I noticed the power XMFR on one unit is much hotter than the other, and wonder what a normal operating temperaure is. After about 4 hours, one channel is >140F (60C) at the top side closest to the 6L6GC's.
At the same time, the other XFMRs are at about 110-130F.
I haven't opened the chassis of these amps, but have replaced all the tubes with NOS that I have retested and matched.
Differences I see are the 6L6GC tubes of the cooler unit are better matched than those of the hotter unit, and the two units have some difference in heat dissipation by air by their locations.
Is 140F or more a normal and safe operating temp? Also, is it normal to have such a large temp differential between two amps?
They continue to sound like heaven...