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Linn LP 12 hum not coming from Bryton phono stage.

I’m getting a pretty significant hum with my Linn Sondek LP12 turntable sitting on top of my equipment stand. My new Bryston MM phono stage does not hum at all when the turntable RCA interconnects are disconnected.

Yes, I have the grounding wire attached to the grounding lug on the phono preamp. I plan to move the TT to the original Sound Organization wall shelf to get it away from the adjacent electronics.

Will moving it to the wall shelf do anything to eliminate hum? What about transitioning to the better "Radikal" power supply and DC motor (the original has the Valhalla board I believe and the AC motor).

Thanks, for any suggestion you might have for things I can check.


edit: I must be tired, I noted that I mis-spelled Bryston as "Bryton". Titles cannot be edited, arghh!

masi61
daveyf's avatar
daveyf
2,874 posts
 
@masi61   Good, sounds like you have a handle on the hum issue. The skating issue may be caused by an incorrect anti-skating force...what tonearm are you using?
noromance's avatar
noromance
9,818 posts
 
Ittok. Test anti-skating. Ittok bearings could be damaged. Check for any looseness.
lewm
13,101 posts
 
The siren rising in intensity is or was evidence of positive feedback, somewhere. Good that you put a stop to it as you might damage your amp and or speakers.
masi61 OP
97 posts
 
@noromance  - The Ittok was tested by Thomas as part of my turntable service and he said is "exceeded spec" with the pendulum test. 
I think the couple of times where the needle skipped onto the paper lable was right as I was about to reach for the tonearm lift and inadvertently jostled the suspension simultaneously. Apparently I drink too much coffee or I am developing a tremor.... but just to play it safe I have been very attentive as I listen and get up out of my chair promptly near the end of the last song on each record side. 
masi61 OP
97 posts
 
@lewm :  I was definitely concerned that the sound was getting louder. 

I plan to message Maze Audio about what happened. When I installed the "Krell Cryo" power cord from the wall outlet to my power conditioner, it did not seem to change the SQ much but I have 2 more of the same power cords. Another one runs from the power conditioner to the power supply for the Bryston BP-26 preamp. It did impact the SQ if I recall. I think it made the sound quality more detailed and dynamics more prominent. 

But why a my phono stage would go crazy just being turned on (without even playing a record yet) is bizarre! Apparently there was some feedback loop that got triggered, but how?
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