Intermittent low hum/buzz


I know this has been covered here on these forums before but I gotta throw it out there one more time . So heres the set up , a dedicated 20 amp circuit on a full space breaker (not a split) so no shared neutral ,number 12 romex into a plastic box which I never use but I figured it would be best for what Im doing here  then finally a hospital grade Isolated ground receptacle.All the cables both AC and signal are all either AQ, Kimber or Acustic Zen ,power conditioner is Torus model 15, power amp Prima Luna evo 400 ,pre amp Prima Luna evo 200 ,sources Aurender A100 ,anolog is Gold note phono pre and Planar 6 turntable with a moving coil cart.So that all seems pretty legit to me so why in the hell do I have this intermittent low level hum or really maybe more of a buzz In the mid range driver? ,oh speakers are Focal Kanta 2,s You have to put your ear right up to the speakers to here it but it’s driving me crazy ,Thanks in advance.

bikeboy52

Showing 1 response by dpop

>>>You have to put your ear right up to the speakers to here it<<<

@bikeboy52 Just wondering if the noise is present, *equally*, in both the L & R channels?

>>>Tubes are noisy. They just are. I’ve tried multiple setups, but the low level noise of tube gear just drove me crazy.<<<

@geof3 Totally with you there. I couldn't take it anymore, and gave up on them years ago.

>>>Pay attention to what is in your rack, some of the hum coupled through the space between shelves from noisy amplifiers and injected it into susceptible components above and below the noise source.<<<

@spatialking I couldn't agree more. Many don't realize this until all equipment is physically placed, and *then* powered up and listened to. When setting up an audio system, I recommend starting with speakers and amplifier hooked up first (with amplifier inputs shorted), then listen for noise. After removing shorting plugs on power amp inputs, connect your pre-amp to your power amp (with one source input shorted). Listening to the shorted input, if there's no noise, continue on with the next component, and listen for noise...and so on. This many times will allow you to quickly identify and isolate which pieces of equipment are not playing nicely together. You may then have to physically move pieces of equipment and cabling to eliminate noise. While performing this staged setup, keep only equipment that has been connected, powered up. 

>>>So possibly its a shielding thing the Kimbers have none<<<

@bikeboy52 Give me a heavy braided shield (for example Belden 1505F or Blue Jeans LC-1) any day over non-shielded Kimbers. I understand Kimber's theory, but in many electrically noisy environments, Kimber RCA interconnects *just can't* reject the noise.