Hum from speakers (1 Viewer)

[carlos f]

I know this issue has been addressed in detail but I have an interesting situation and wanted some advice.

I know I have ground loop issues. I've always had bar on tv and hum from tv. Doesn't bother me much but i'll address it soon.

My issue now is that I just hooked up my Rotel rsp 1066

to my system and now i'm getting nasty hum from all speakers. Before i had sony es 30 receiver, rotel rmb 1066 amp and no hum at all. Now i have rotel rsp 1066, rb 1070, and rmb 1066 and getting the hum.

I don't think the ground loop from cable tv is causing this since it never affected my sound system before.

Am I missing something here?

 

[Elbert Lee]

I would still try removing your CATV feed to any of your components. Something could have affected your CATV that was not there before. Could be possible that a CATV tech may have inadvertantly made some changes to your cable outside your home.

Elbert

 

[brian a]

You also might try a cheater plug on your amp. That solved the problem for me in the past with a Ref 20. and ATI1505. I'm still using it with the 1066 / 1505 / and 2 monoblocks.

 

[Will Gatlin Jr]

I had the same problem coming from one of my two-ch NAK amps. I have two NAK PA-7A II power amps (225 watts), and a NAK PA-5A II power amp (150 watts). Two of the amps have a 2 prong power cord and the other has a 3 prong power cord. If I take the cord with the 3 prongs in it and plug it into any of the thre amps, I get a hum. If I take any of the two cords with the 2 prongs in it, no hum at all. On the power cord that hums, if I put a CHEATER plug on it, no hum!! But we all know the cheater plug thing, no good!!

A lot of the guys told me it was Cable TV interference, but it wasn't. What I did was brake off the negative ground on the 3 prong plug. I taped up the little hole with electric tape, no humm!! A lot of the guy told me this was dangerous to my power amp if something ever happend.

I took all 3 power cords to my local electroics shop. I told the electrican my situation. So far so good...I won't stop looking for that 2 rong plug. Good luck!!

 

[MiltK]

Are you using halogen lighting with a dimmer? Make sure there are no dimmers on the same circuit. I eliminated a very loud buzzing/humming emanating from my speakers by changing floor lamps to one that uses standard bulbs. Evidently the triac device used by dimmers will cause ground loops.

 

[Steve Zimmerman]

I took all 3 power cords to my local electroics shop. I told the electrican my situation. So far so good...I won't stop looking for that 2 rong plug. Good luck!!

Will, it's NOT the cords, it's NOT the amps. You have a ground loop problem. That's why you only hear the hum when your ground (using the three prong plug) one of the amps.

The best solution is to find the source of the hum rather than using a two prong plug or a cheater.

--Steve