[RSN]

Cross-posting this with Receviers/Amps forum because I just noticed this area fielded these types of quesitons. Sorry for the repitition if you read this post already.


I wanted to check with our community on a humming issue that just sprung up on my system.


The setup:


Receiver: Denon 3805

TV: Samsung HDTV 1080p DLP

Blu Ray DVD: Sony BDP-S550 (HDMI to TV/analog out to 3805)

Satellite: DirectTV HD DVR Receiver (HDMI to TV/optical out)

Speakers: B&W 600s (602 s2 fronts, 601 s2 rear, CC6 S2 center, no sub)


Everything is plugged into the same surge protector.

Running fronts, surrounds and center from DVD player's multi channel outputs via RCA cables to allow S550 to handle audio decoding since the 3805 can't do it.


Except for the S550 (thank you Santa), everything in this system has been playing together nicely for the past 3-4 years. However, when I added the S550 to the mix, the speakers began to hum. I disconnected the RCA cables running from the S550 to the 3805 and *poof* no hum.


I used some basic RCA cables (read: free cables that we all get in every A/V component that we have ever bought and end up storing in a shoebox) I had laying around as a stop-gap until my cables from Monoprice come in this week. Are these the weak link or do I have a grounding problem? Is there such a thing as a grounding problem with a DVD player? Forgive my ignorance, I've never encountered this issue before.


I am hoping that replacing the flimsy cables I had laying around with some quality cables might solve the problem. However, I wanted to run it by some other HTers and get your opinions. If it is a grounding issue, I want to make sure I handle it correctly.


Thanks in advance for any insight you can offer.


EGM

 

[Ratman]

IMO...

wait till you get your new cables before going into a "cross-post panic".

 

[RSN]

Wouldn't classify it as "panic" more obsessive curiosity.

What can I say, I used to be a Boy Scout and always like to be prepared.

RSN

 

[burnsniper]

If the S550 has a grounded plug (3 prong) and everything else doesn't, then grounding is probably your problem.

 

[Yosh70]

If it is the BD player, you can get a 2 prong adapter to see if the hum goes away.


Or you can be cheap like me when I had a humming problem with my powered monitors for my computer, I just broke off the third prong.


Not the best way but, meh, it worked.

 

[LTD02]

i seem to recall that a culprit for hum is multiple grounding sources, such as one coming in through the television cable line and another being from grounding on equipment. burnsniper may have hit on it, if you already had one source of grounding and then added a power cable to the mix that has its own ground that would be more than one source and could cause hum.


there are devices that you can plug your equipment into that then plug into the wall that fix this problem. i forget what they are called. probably something like "hum eliminator". ;-)


the cheap rca cables should not be the problem.


hum should only occur in cables that have really long runs or are subjected to very powerful electromagnetic fields. if you have your rca cabling mixed up with your power cords, there is a small chance that could be a problem too.

 

[Ratman]

It very well could be a bad cable or cables from the shoebox. Once you get the new ones maybe it will be resolved. If not, you've elimimated the potentially obvious and we can go from there... in one thread.


Why have everyone spin their wheels?

If you want to be "boy scouty", disconnect the 500 ftom the AV receiver.

remove the optical between the DVR and AV receiver.

connect the DVR (temporarily) using red/white to AV receiver.


Got hum?

 

[RSN]

The S550 has a two-prong plug, so there shouldn't be a grounding issue there.


Rat-


I'll give that a try and see what happens.


Thanks for all the input guys.


RSN