silvertone 1482 hum and hiss
I have a Sivertone 1482 that I restored and rehoused (There was no cabinet with the amp when I bought it.
Amp was working perfectly and was dead quiet untill last week.
I connected a preamp with an effectprocessor (just to test that) that suddenly started to oscillate. Not too loud and I have turned it down asap.
Ever since I have a hum and hiss in the silvertone.
There is a slight hum with the volume down. It gets louder when I turn the volume up and a hiss is added. It is the same on both channels.
- changing the preamp tubes does not make any difference. I have used a couple of different tubes.
- changing the power tubes does not make any difference.
- I have checked the voltages in the amp and they about what they where and in the area of what the schematic indicates.
- no change in the hum when moving parts and wiring with a chopstick.
- I am feeding the am on a 220-110 convertor as I am in Europe. I have done this eversince I have the amp. The problem was not there before.
- No dc reading after the caps in the amp.
- caps are original. I know that would be one of the first to change but I happen to like the sound of the originals.
- can capacitor is not original but is possibly from that era. I have chnaged it before with a weber can cap but I did not like that sound. Too harsh.
But I did not have this problem before and I was using the "original" can cap at that time.
The question is?
Could the hiss and hum come from that oscillating effectprocessor? Could that have damaged something?
Where could I be looking too solve this?