Background noise

[hiro]

I've got a RSP-1066 and a RB-1080 as amplifier (added with a RMB-1095 for multi-channel play back). I use a Denon DVD-3800 for the source.
When installing them, I was very pleased to listen music in stereo mode till a few minutes ago when a background noise appeared :evil: ! I precise that the RMB-1095 is still unplugged from sector (installation not fully completed but I'm too impatient! ops: ).
Bloody hell! What happened?
I think this unpleasant noise comes from ground problem and I revised my all connections.
The bug appears whenever I connect the RB-1080 unbalanced inputs with the corresponding outputs independantly from my Pre-amp or player!
What on earth is the problem? How can I fix it?
Lots of thanks in advance.

[Andrew Pratt]

It does sound like a grounding problem. I'd start by unplugging all the other components and then add one at a time until you find out exactly which one is causing the problem. Are these all plugged into the same power bar or different sockets?

[hiro]

I'd start by unplugging all the other components and then add one at a time until you find out exactly which one is causing the problem

It was what I did: I isolated my pre-amp from my denon (my only source for the moment) by unplugging the multichannel inputs and my digital coaxial cable but the problem's still going on!
I'm quite sure that it's a grounding conflict because the noise only appears when I use the RCA inputs of the RB-1080 whithout any sources added on the RSP-1066.
Is it possible that the lack of ground connection in the pre-amp power cable could be the reason for?
In this case, how can I fix it?
Just for information, I use the same power bar for all of them.

[SayersWeb]

Do you get the noise if cables are connected to the amp but not connected on the other end? What else do you have plugged into your power strip? Unplug everything but the amp and preamp and then try the connections.

Also remember that the circuit you plug your equipment into may feed other outlets in your house. Could another device be causing the problem? Did you plug any new devices in your house around the time the problem started? New clock, lamp with dimmer, powered subwoofer. etc?




Sayer - Musical Creations and Home Page

[hiro]

Thanks a lot for your help and for telling how to proceed.
I've finally found that only cables connected to the TV lead to this unpleasant noise: s-video and scart one!
Then I isolated the TV to find where the ground loop could be and the problem appears only when the TV cable is connected.
Do you think that if I use a filtered power strip where it's possible to connect through the TV cable, the issue will be solved?

[SayersWeb]

hiro -

That very well could help. I'm wondering why your cable isn't grounded properly. This is coax cable from your cable company? Can you run it through your VCR first to see if that makes a difference?

I take it that you go from the TV out to the RSP-1066? Is the TV plugged into the same electrical outlet as the RSP-1066? If not, you may want to try it to see if that takes care of the problem.




Sayer - Musical Creations and Home Page