Cheater plug did not make a difference. Hum was still there.
I swapped the power tubes and it is possible the worse side
I swapped the power tubes and it is possible the worse side
Amplifier Hum - Only Amp Connected
I have read many threads on here about various amplifier hum.
I recently bought a used tube amplifier. When I connected the amp and turned it on, I immediately heard a hum from the mid-range driver of both speakers. The hum is audible even if the pre-amplifier is turned off/muted. In fact, I unplugged all interconnects from the amplifier and still heard a hum when the amp was on. I then unplugged the the interconnects and unplugged everything else in the room from the outlets (turntable, pre-amplifier, TV, and cable box), so that the only thing in the room connected to the wall was the amp. I still hear the hum from the speakers when it is only wall>power cord>amp>speaker cable>speaker.
This has to mean that it is a problem internal to the amp, correct?
I recently bought a used tube amplifier. When I connected the amp and turned it on, I immediately heard a hum from the mid-range driver of both speakers. The hum is audible even if the pre-amplifier is turned off/muted. In fact, I unplugged all interconnects from the amplifier and still heard a hum when the amp was on. I then unplugged the the interconnects and unplugged everything else in the room from the outlets (turntable, pre-amplifier, TV, and cable box), so that the only thing in the room connected to the wall was the amp. I still hear the hum from the speakers when it is only wall>power cord>amp>speaker cable>speaker.
This has to mean that it is a problem internal to the amp, correct?
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- 24 posts total
jdpawnbroker OP6 posts Did you put a piece of tape on the bottom of the cheater plug ground tab, or over the trim screw that hold on the electrical outlet cover plate, so the ground tab does not make electrical contact with the metal screw? The trim screw is electrically connected to the equipment ground. |
This sounds to me like a power supply problem such as a failing filter capacitor in the power supply. Such a part can indeed cause more hum in one channel than the other but the problem would be in both. Sometimes you might be able to get it to stop humming for a little bit by simply turning the amp off and on again, but only sometimes. My recommendation is to seek service on the amplifier. |
- 24 posts total