Buzz on AV2 into NAC282

Posted by: Paul Erricker on 25 May 2009

AV system - DVD5, AV2, V175, V145. AV2 into NAC282 (with NAPSC and HiCap), NAP 200.

I'm going nuts trying to isolate an annoying buzz that's recently emerged in my set up. When the AV2 is on and the NAC282 is switched to AV, I get a buzz through the main L & R speakers. No buzz on any other NAC282 source or any of the surround speakers. The buzz increases and decreases at different times of the day but not consistently, from listenable to unlistenable (had to stop watching a movie last night !).

Have tried changing mains cables, cable from AV2 to NAC282, isoltaing different parts of the household consumer unit. My old NAC202 produced the same buzz so it doubt its anything to do with the stereo pre-amp. I've even removed all sources into the AV2. I thought it was the new dimmer lights in my room as the buzz increased as I dimmed the lights. Had them removed and I still get a buzz !!

Any suggestions welcome for a guy who can't now listen to my entire AV side of the system.

Many thanks
Posted on: 25 May 2009 by Massimo Bertola
Paul,

welcome to the forum but I'm welcoming you with a problem more than with an answer...

I mentioned in another thread an issue with my AV2: I moved from a very nice stereo system (CDX2/XPS2/HiLine/202/HiCap/Napsc/200/SBLs) to a multichannel one (DVD5/AV2/175/200) in which the AV2 was acting as a preamp too.

As soon as I moved to this new, preamp-less system I began to have ticks and TOCKS each time I switched the motorized roller shutters on. Nothing helped. Then, a few weeks ago I tried a preamp (feeding the AV2 into it via the Unity Gain configuration, much as I think you do yourself) and apart from the soinc results, the ticks and tocks disappeared - or, more precisely, they disappeared in the front L+R (that pass throu the preamp) and remained to a certain degree in the surround + center, that go directly from the AV2 to their power amp. The same applied when I changed Nac 112 and 200 with a Nait XS.

So, I have an idea that something inside the AV2 is slightly wrong regarding grounds, or maybe that it's more susceptible to noises even, in your case, when a preamp is present.

From what you say, seems an external noise coming in, the kind refrigerators and lamps do.

Have you checked all the fascia in the cables? Are they connected the proper way? Are all grounds ok?

I'm sorry I can't give you more help, but hope that someone will solve your problem.

Massimo
Posted on: 25 May 2009 by Chris Murphy
See your dealer. There is an earth link that can be removed in the AV2. This may be your problem.

Cheers,

Chris.
Posted on: 27 May 2009 by Signals UK
Paul, I know we didn't sell you any of this kit, but you have been to see us, you're not far away and we can probably sort it out.

Alastair
Posted on: 28 May 2009 by Paul Erricker
Well. What can I say. Thanks to Alastair and Andy at Signals in Ipswich, the problem is sorted. The buzz was being created by the FM cable going into my NAT05. I'm not sure of the full tecnical explaination, but it seems related to the FM/TV wall socket which runs from an amplified aerial splitter in the roof. Somehow this was picking-up interference from several household appliances and transferring this into the AV2 to NAC282 set-up.

Anyway, I'm now a happy bunny as I can watch a film listening to only what the Director intended me to hear.

Thanks Signals !
Posted on: 28 May 2009 by Signals UK
Excellent news. Andy will be pleased to hear this when he gets in tomorrow.


Alastair