Noise from surrounds 805s

[Cooldmitriy]

Here's my setting : 2 x 804s, HTS4S, 2 x 805s (surrounds), ASW750, ROTEL 1056.

I just finished putting all the components togeter several days ago.

Last night I decided to give it a test run by playing Star Wars (part.3). Everything works fine, except one thing. I notieced slight noise comming for surrounds 805s. It's more noticible when a dialog takes place and there's no music playing on the background.

Maybe I need to callibrate my Rotel 1056 to eliminate that noise. Maybe I need to set another dB output level. I am not sure.

Any recommendations?

[Mark_C.]

First, I would hook them up to the front and play some music to make sure there is nothing physically wrong with the speakers.

[dan87951]

What kind of speaker cables are you using? Are the speakers cables near anything electrical such as a power outlet? Could be electromagnetic interference abd the cables are picking this noise up or cross talk if you cheaped out on the cables.A good cable will have good shielding to prevent this or will be twisted pair which prevents cross talk because the signals are 180 degrees out of phase and the noise just cancels out. Hope this helps.

Dan

[Cooldmitriy]

Hello dan87951,

I use Monster Cable in-wall speaker14 gauge two conducter wire. Both wires run through the basesment into the living room. There are no electical outlets nearby.

Could it be an issue with incorrect crossover setting in my ROTEL 1056?

[audioqueso]

Have you tried any other DVD? If it's still the same, try swapping the speaker wire on the Rotel so that the front signals are sent to the 805 and rear signals sent to your 804. See if you get it then.

[Cooldmitriy]

Guys,

this is more hiss than a noise. Could it be a faulty ROTEL unit?

[audioqueso]

Did you try what we suggested?

[Cooldmitriy]

I tried another DVD and the result was the same. I will try tonight to swap front and surround cables per your request.

I also read several posts in ROTEL forum about similar hiss comming from speakers.

[dyazdani]

First thing you always do is to find out which component it's coming from. That is the point of Mark and audioqueso's suggestion to swap the cables around and try the surround channels on your front speakers. If the hiss goes away, then it is something with your 805s.

If the hiss moves to your front speakers, than the hiss is coming from one of the upstream components, probably the Rotel. Could be a ground problem or a faulty interconnect. I've had both issues in my system, not too difficult to track down if you go step by step.

Let us know what you find.

[Cooldmitriy]

dyazdani, thank you very much. Once I get back home I post the result here.
I've heard stories about hiss issues with ROTEL, but still can't believe it.

[dan87951]

I had a Rotel RB-1080 that had a hiss when ever my tv was plugged into the cable jack in the wall. The myth about the Rotel hiss is true and got a replacement unit promply from my local dealer and it fixed the problem. Good Luck with it.

[audioqueso]

That doesn't sound like a Rotel only problem. I've heard lots of people mention hiss once they connect their cable to the system, and the answer is and always will be 'grounding'. Cooldmitriy, if you find that disconnecting your cable tv makes it go away, try using better shielded cable and ground your system properly. IF it's the whole cable tv thing.

[dan87951]

That doesn't sound like a Rotel only problem. I've heard lots of people mention hiss once they connect their cable to the system, and the answer is and always will be 'grounding'. Cooldmitriy, if you find that disconnecting your cable tv makes it go away, try using better shielded cable and ground your system properly. IF it's the whole cable tv thing.

This problem is more persistent with Rotel equipment expeically there amplifers. Just do a search on google that will justify my statemtents.
Ground your system properly? Please elaborate?

[audioqueso]

Oh no, I'm not saying that your statement is untrue. I believe you. But those symptons sound like grounding issue at some point. Perhaps Rotel is more susceptible due to the way they're built. Let me explain.

Whenever your introduce an external source (power line, signal lines, etc), your system will be susceptible to noise and electrical interference. Jitter, excess bleeding, distortion... whatever it is, can all be audible through vibrations. And since the sound waves we listen to coming out of our speakers are actually vibrations, we will in turn be able to hear these flaws. Most networks, systems, electrical components are built to handle these. The electrical wiring in your home is grounded properly, your Rotel will have certain components properly shielded to resist/protect, the power cable connecting the Rotel to the electrical outlet even have the 3rd prong to ensure the equipment's electrical path is grounded as well. CD/DVDs are digital so unless you're using analog outputs from the CD/DVD player, the only thing you should really need is the power ground from the cable. Even the wire ran on the outside of your house for your cable tv is grounded to eliminate as much interference as possible until it reaches your house (or the cable company's last point of responsibility). However, there are sections that are flawed and open to noise and interference. Starting off with the cable company's wires. Their demark point (the last wiring point or the point where it enters a building/structure where it's their responsibility) might be 30 feet away from your wall of your house. At that point, those inspections are not strict for housing/apartments. They only check for connectivity. So that means some regular joe could have done a piss poor job and not install it properly. Then you have all the rca jacks in the house that, as we've all seen at one point or another, are installed poorly as well, loose connections, etc. There's lots of little things that a lot of times are not done properly. By the time it reaches your stereo you could have 50 feet or more that is susceptible to noise and other interference. This is why a lot of times you here people that have hiss find it comes from their cable connection. In this case this is why the speaker wire DOES MATTER (Shouting to all non-believers). If you find that you are receiving hiss from the cable connection, try a good quality shielded coax cable to help eliminate the noise, or try externally ground the cable receiver and/or daisy chain that ground to the Rotel. It's lots of little things that can build up noise or other interference to the point where it is audible.

That was long... sorry. But does that make more sense to you now?

[audioqueso]

Mark, have you even tried the cable swap that Mark C. and I have suggested? You really should to further isolate the problem.

[Mark_C.]

This is really a process of elimination. That's why I suggested swapping inputs. Plug the rear speaker connectors into the front inputs of your receiver/amp and check to see if you are still getting the noise. We are talking about hiss here, right? Or is this noise something else?

[bluesfan]

This is really a process of elimination. That's why I suggested swapping inputs. Plug the rear speaker connectors into the front inputs of your receiver/amp and check to see if you are still getting the noise. We are talking about hiss here, right? Or is this noise something else?

I had a demo at a dealer this morning and there was buzz from the speakers on no input sound (1068/1095).

I also demoed a Denon 3806 and can say there was no speaker buzz/hiss/hum noise even on full volume.

Personally I don't think this is very funny and wonder what Rotel has done to make it so susceptible so feedback or earthing problems.

[Kens1]

I have the 1056 & 1080 combo - no buzz, no hiss. Equipment is plugged into a power bar that is plugged into a normal outlet - go figure.