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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
masi61 OP
97 posts
 

Thanks for your interest @noromance  & @daveyf .

I had a hunch that the Maze Audio Krell cryo power cord that I had running to my Bryston BIT-15 power conditioner from the wall might in some way be contributing to the wild "siren" sound loop that went nuts when I turned on the phono input. So I put the stock cord back on. The wild shrieking sound mostly went away, then after a time it appeared to completely dissipate.

The "Y" connector taps into the umbilical power cord that runs from my Bryston outboard power supply and BP-26 preamp. It does appear to that everything is operating normally now. My tonearm cable has not one but two grounding wires which are both connected to the Bryston phono stage. Other than RCA interconnects from the phono stage to the BP-26 preamp I do no see any option for an extra ground wire to be run between the 2.

Yes Thomas tested my LP12 for hum and it actually had NO hum issues before or after the installation of the Radikal power supply and motor upgrade. Right now I'm just beginning the process of listening to a bunch of my old and new vinyl records. The sound quality is really, really wonderful so far. I am out of practice with my vinyl care and have lots of questions. I'll probably continue to write about my experiences with all of this. Strangely, with the Adikt cartridge twice now at the end of the record, the stylus just kept on going and skated right onto the paper disc in the middle. I did use the tonearm lift quickly both times so hopefully the stylus is not damaged by this.

daveyf's avatar
daveyf
2,857 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
9,710 posts
 
Ittok. Test anti-skating. Ittok bearings could be damaged. Check for any looseness.
lewm
12,849 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. 
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