Humming when playing records

Posted by: Terence Chong on 14 January 2003

Hi guys, just a bit concerned. Frown

I get an audible hum when playing records. The level from the preamp is about 11 o'clock when this happens.

Someone told me it is from the phono stage. How true is this? Anyone with similar problems?

My LP12/Valhalla/OL RB300 goes to an extenal phono stage (Trichord Dino) then to the NAC 72 via RCA to DIN connection.

My cartridge is a Denon DL103R (Output mV = 0.28)

Thank you for your feedbacks

All opinions are solely my own and not forceful in any nature.
Posted on: 14 January 2003 by Idris Mohammed
Hello Terence,

I had a similar problem when I first installed my FM 222 Phono stage. I had loud hum when volume pot was at about 12 o'clock. The problem was fixed when my dealer did some dressing and adjustment of the tonearm cables and earth leads. The difference was like night and day. You should try this first before attempting other more painful remedies. Good luck.

Regards,

Idris Mohammed, Singapore.
Posted on: 14 January 2003 by Laurie Saunders
a friend had a Michell Iso...this had a hum problem. I experienced hum when I tried the Tom Evans Groove. I think that a possible cause was the plastic cases, ie lack of screening which made them very susceptible to hum if placed anywhere near a transformer, or mains leads. The hum was very much reduced by careful positioning. It could also be an earthing problem. Naim kit uses its own special earthing system...you are taking a bit of a chance when mixing Naim amplification with others`.The problem may lie either on the arm side, or between the phono stage and preamp. This could be a tricky one to solve..you could try placing you phono stage inside an earthed aluminium box. Sorry if the above is not very helpful

best of luck
Laurie S
Posted on: 15 January 2003 by Terence Chong
I think it's either the positioning of the Dino or the RB300's internal wiring. Thanks anyway for all of your invaluable feedbacks.

All opinions are solely my own and not forceful in any nature.
Posted on: 15 January 2003 by Rockingdoc
some cartridges are more succeptible to hum also, e.g. my Ortophon Rohmann is much worse than my Linn mc carts for hum. Generally, positioning the phono stage as far away from everything else as possible gives the best result.

malcolm