Hum on Tube Amp - Can't find source
I have a hum (60hz) I can hear on my speakers and it happens with my tube monoblocks (either of them). With or without interconnects, it even happens on either amp (have tried one at a time) with every circuit on the house tripped/disconnected, every other component disconnected from the wall (including the Internet/CaTV line) and no interconnects.
One amp has it as soon as it warms up whereas the other one is intermittent.
Hum X doesn't solve it, iFi Ground defender either, AVA HumDinger on powerline doesn't solve it either.
I have replaced the tubes and both amps were just tested at the factory. Replaced the circuit breaker, tightened every wire on the breaker box, checked and cleaned all connections to ground rod. Added a hum eliminator to the internet line.
Hum cycles a bit with the tube glow matching the cycles.
I'm waiting on the power company to come check the power coming to the house.
Thoughts?
@dpop Once the noise starts you can't bias them as the voltage cycles. Having said that, they are right at 298-303 on all tubes (after many tries before the noise starts).
@jerryg123 Thanks, I read the article and the discussion about it here, on AK and other sites. It was highlighted on a post before. He describes a change in sound but not the noise I have present. His solution was to add Powerplants. I am hoping to address the issue before that kind of investment. |
@wsrrsw typing from Phone is always a challenge, I appreciate your time! I did try a long extension cord to an outlet which is on a different panel (I have 6 panels at home plus the main panel at the interconnection with the utility). Problem was present |
