TSE help

[evanc]

After a few months not using my TSE I decided to put it back into my system a few days ago. I had forgotten how nice this amp sounds.
My preamp runs directly to the TSE and to a minidsp to eq the signal to a separate amp for the woofers.
Well last night I mistakenly turned off the minidsp before I turned off the amps. There was a very loud thump. It was late and I went to bed. Today when I turned the system on the TSE is humming through the speakers. Not very loud, but a hum that is noticeable and was definitely not there before. Same in both channels. I took the amp out of the system and played it by itself, same result...hum. I checked the voltages and all seems ok. The only thing I find off is the heaters for the 5842 tubes are at 5.7 volts.
Any ideas where I should look?
Thanks, Evan

[rknize]

Seems unlikely you could have caused damage by doing that. The low heater voltage is relatively normal, especially if you are not using a Allied or Hammond power transformer. George has a dropping resistor on the heater supply to compensate for the "hot" secondaries on those.

Are you using 300Bs or 45s? What is the heater supply voltage going into the regulator?

[evanc]

Russ,
Thanks for taking the time to give me a hand. Maybe it started humming while it was playing and I didn't notice it until I started it the next day. It runs 45 tubes. The input to the regulator is 3.4 volts. 2.5 out. The Hammond transformer has a line in for 125 volts that I use. This gives me 275v bplus with my set up. If I use the 115volt line in my b plus is well over 300 volts even with a very small c4. I'll check out more after work.
Thanks, Evan