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Tube Pre-amp Phono 60 Cycle Hum - Big Time

I have a Linn Sondek LP-12 with Valhalla which I just setup for the first time. It came with BNC connectors so I had to get 2 RCA adaptors which fit to the MC of my tube pre-amp.

My question is this; I attached everything on the Linn Sondek to the pre-amp and got significant 60 cycle hum in the phono stage. Even when I disconnect the turntable from the pre-amp I get tremendous hum on the phono stage when
turning up the vol. control. There is a very slight hum on CD and Tuner, but not bad and nothing like in phono. Everything goes into a Monster Power 5100 power conditioner. Any suggestions on what is wrong and how I can fix it?
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rcprince
3,070 posts
 
Is there a grounding wire from the arm that you can attach to the preamp's chasis? That may help.
sidssp
1,077 posts
 
One possibility is that your phono amp is in close proximity of an electric magnetic device - a transformer for example, and is picking up hums from there. Please try to move the phono amp around to see if the situation improves.
blub
8 posts
 
I was experiencing major hum on phono stage even when phono wasn't hooked up. Unplugged my tv cable from the wall, hum gone!
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