Buzzing After Moving Components

[jimmyp58]

I am in the process of getting a new A/V rack but until I settle in on which one to get, I had to take care of the WAF with my current rack/layout. I have two tower racks currently, each one flanking my RPTV/HDTV. Each tower has a series of components plugged into a Monster Power HTS 5100; each 5100 is plugged into it's own wall outlet. Essentially with my rearrangement, I moved tower 1 where tower 2 was and visa versa and moved components around in each tower. Prior to this move, I didn't hear any buzzing coming from any speaker.

In tower 1, I have my HTS 5100 fed with a Bryston 4B SST amp, Rotel RB-1050 amp, Rotel RMB-1095 amp, Rotel RSP-1098 pre/pro, Sony MDS-501 MiniDisc recorder/player, and Denon DVD-2900. Again prior to the move, all these components were plugged into the same 5100 on the other side of my RPTV/HDTV but were arranged on different shelves and I didn't hear any buzzing.

I turned on my units after moving and I heard a god-awful buzzing from my center channel speaker and my surrounds; I could hear a VERY faint buzz coming from my front channel speakers. My fronts are powered by the Bryston and the center/surrounds by the RMB-1095. I unplugged and replugged all of the components to see if this would remedy the problem. No luck. I plugged my amps directly into the wall outlet (rather than the 5100), no luck again.

I called my HT rep and he suggested it was a grounding problem, which is not uncommon with moves and that I should convert my three-prong devices to two-prong with those $0.69 adapters. It worked except for an extremely soft buzz from the center channel speaker.

So, why did this work? Also, could this be a problem because I am NOT using the three-prong? I notice that on my 5100's readout, the "Ground OK" light is no longer lit. Is this a problem? Is using these adapters just a "bandaid" and I should really having an electrician take a look at what's going on?

Please advise fellas...you guys are the pros at this.

Thanks...

Jim

[Scarp]

My suggestion:
- remove all equipment from the racks
- then build up one at a time, so put your 1098 there and one amp (for the front channels) with the speaker connected to them.
- turn on and listen if there is any buzzing.
- then step by step add equipment, so next add an amp for your center (maybe even remove the amp for your fronts again) and test again.

This might take a while, but it would be possible to find the main source.

Besides that check for the routing of your cables. Make sure mains cables are well away from interconnects and speaker cables. Check especially your center, since you mentioned that the most noise come from there.

Using tricks with those plugs isn't recommended, so only use it as a last resort.

[Danbry39]

I agree with Scarp, especially that your interconnects, speaker cables stay away from each other. I'll add one more: The power cords. Try joggling those a bit and see if it doesn't change the character of the hum you're hearing from the center. Check closely that the center channel cable is free and clear of any power cables. I've read that they radiate an electrical field which can impact other interconnects.

I've had problems similar to yours and, on at least a couple of occasions, it was relieved by rearranging the jumbled mess behind my gear.




Keith

[Andrew Pratt]

By removing the ground pin on those plugs with the "cheater" plugs you've now isolated the grounds..which can help remedy the problem but should one of those pieces of equipment have an electrical problem what would normally flow down the ground pin will now wait for someone to touch the case and you'll be the new ground...obviously not a good solution for you! These are illegal in Canada which gives you some idea of how dangerous they can be. Now there's likely no need to worry since problems like that are rare but I wanted you to realize exactly what could occur.

Since it seems that there wasn't a problem before when the gear was plugged into the other wall socket and that these two racks are close together could you not simply run an extension cord from the good plug over to the new rack? One other thing when you plug your HTS directly (no cheater plug) into the "bad" wall plug does the ground ok light come on?

[jimmyp58]

Before leaving for work this morning, I disconnected most of the units from the HTS 5100 and the corresponding interconnect cables from the RSP-1098. I physically removed the MiniDisc unit from the shelf. Still heard the very faint buzzing but it is only now with the center channel speaker --- so I think this is at least some progress. I took the cheater plug off the HTS 5100 and plugged it back into the wall socket and the buzzing actually got louder. The "Ground OK" light was lit though.

I'm set to go home in a bit and will be working on this in the afternoon. Could the problem be as simple as the speaker cable from the center channel has a short in it?

I'll keep you posted on what happens.

Jim

[Scarp]

A little bit white noise is common from speakers, but you should only be able to hear that when really close (> 1 feet or so).

Check your speaker cables also, check connections ...

Its a tedious job

[jimmyp58]

It ONLY took a few hours but I am back to some white noise when I put my ear right on the speakers. And, I have all the cheater adapters off. My HTS 5100 has the Ground OK light lit. Life's good again!

I still hear a very, very faint high pitch buzz from the center channel's tweeter but I have to have my ear right on the tweeter to hear it.

Thanks fellas...

Jim

[lcajiga]

Hi Jim, may you please tell us from all the things that you did, what helped more?

Regards,
Luis




Regards,
Luis

http://www.luiscajiga.com/HT.htm

"It is not what you see and hear...it is how!"

[Azeke]

Jim,

I own a Monster 2600, and I found that I must connect my plugs especially my RMB 1095 to the proper outlets of the 2600, this really minimized the white noise (almost nill).

Hope this helps,

Arman

[jimmyp58]

As I mentioned, I am down to white noise which is inaudible unless you put your ear right on the speaker. I followed Scarp's advice by breaking the whole system down then built it back up one component at a time. There must have been some signal bleed from somewhere that caused the problem I had. Whatever, I am a happy dude again.

I am going to take this one step further though. Just like all of you, I've got a rat's nest of wires/cables behind my unit. I just visited the Smart Home website and bought some cable management device to organize my power cords, interconnects, and speaker cables. Not only will this tidy things up, but perhaps will let me segregate each type of run to further minimize signal bleed.

I will report back to let you know how this worked out.

Thanks again for the input.

Jim