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Transformer of the amplifier hums with TV on

ToKillTime

Member
Joined
Sep 30, 2021
Messages
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Hello all,

I own a Rotel RA-1592 amplifier since recently. This one works wonderfully and I'm actually very happy with it.

However, what I have noticed (and is somewhat annoying) is the fact that the amplifier hums when the TV (LG Oled) is running. The amplifier is located under the TV. Both Devices are connected with a toslink cable.

I was then able to quickly determine that the toroidal transformer of the amplifier was emitting a hum.

The interesting thing is that the hum is not even, but gets stronger/weaker when the picture on the TV is bright or dark.

The two devices are connected to a multiple socket, in which a PS 5 and a telephone are also connected.

First attempts to solve the problem have been unsuccessful so far:
- Turn the plug
- Devices to separate sockets
- sheath filter
- New power strip
- TV cable away

The question is, what else can I do? Is it possible that the transformer of the amplifier is not properly shielded and is consequently disturbed by the TV?

I am very grateful for any tips and help!

Kind regards
ToKillTime
 

Jbrunwa

Senior Member
Joined
Mar 13, 2021
Messages
301
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339
Location
Seattle
Try to plug the tv into an electrical outlet that is on a separate circuit breaker from the rest of the components and listen if the hum stops.
 

DVDdoug

Major Contributor
Joined
May 27, 2021
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I had the same problem with an old rear-projection TV and somebody here recently reported a similar issue when they run their microwave...

The prevailing theory is that there is a DC offset on the power line. There are some fixes for this, but you'd have to search.

BTW - My humming/vibrating transformer was a "regular" laminated transformer. And there was no hum in the signal, just mechanical vibration of the amp, and nothing "bad" happened even though it seemed like something was going to start smoking or blow!
 
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