2. amps-preamps
  3. 191496-195982

Speakers low pitch humming, is it normal, or real issue with preamp?

I shall appreciate your experienced inputs. I just purchased pre-owned audio set, all used for 2 years and in good conditions. McIntosh Preamp C53, Amp MA462, B&W 805 d5. I noticed whenever the preamp was turned on, there is a very low humming noise coming out from speakers, can hear it only when get my ear very close to the speakers ( so probably it does not affect my normal music listening which mostly covers the noise). When I tried turned off preamp, and keep the power amp on, there is absolutely no noise, so the noise definitely comes from the C53. When I connect to the DA2 using digital input with coax cable, the noise is more pronounced (even without streaming source). I am a newbie for audio, am I too nervous, or this is normal since no component is perfect?

randywong
soix
9,665 posts
 

Could be a ground loop.  You could try using a cheater plug to lift the ground on the preamp, amp, etc. and see if that eliminates the hum.  Not a long-term solution but at least you’ll see if that’s the problem and then go from there.  I suppose you could also try adjusting the positions of your power cables if certain ones are crossed — not likely the source of the problem but it’s free and good to rule out.  Just a couple thoughts FWIW, and best of luck in tracking down the problem. 

rick_n's avatar
rick_n
218 posts
 

I agree with @soix could be a ground loop.  I would try his solution and see if that eliminates the issue.  If it does, try plugging the pre into an outlet on a different house circuit.  

mofojo
2,304 posts
 

If you can only hear it from a few inches away I wouldn’t worry about it. The only setup I ever had that was Completely silent was a Lyngdorf integrated. If you sit in the quiet room and really listen and can hear something then that’s a different story. 

More to discover