Noises on AV2 with Unity Gain
Posted by: djorg on 16 July 2010
I have some problems with my 112x!!
I use it with a Denon 4310 and I have an abnormal level of noise with unity gain on AV2. Others inputs are OK, and I use a 3 meter long RCA between the Denon and the Naim.
I read that my RCA connect might be the problem, and that some resistances might solve my problem...
Any details, or others suggestions?
Thank you
I use it with a Denon 4310 and I have an abnormal level of noise with unity gain on AV2. Others inputs are OK, and I use a 3 meter long RCA between the Denon and the Naim.
I read that my RCA connect might be the problem, and that some resistances might solve my problem...
Any details, or others suggestions?
Thank you
Posted on: 17 July 2010 by Geoff P
I have been messing around with AV receivers connected to my Naim system for front channel replay for quite some time. I have never been able to get an always hum free connection with unity gain enabled, and that applies all the way from the early days on a 112 to now on a 552.
The harsh fact is that it is very easy to end up with earth loops where the signal has two seperate earthing points at the same time. This is most often due to the AV part of the system acheiving earth thru' your TV/Sat or cable 75ohm coax connection.
While unity gain is supposed to help it often doesn't fix this problem. I have found the best way is to cancel unity gain on the naim pre amp and always set volume when using the AV input to a fixed position such as 9.00 or 12.00. You then run the speaker volume setup on the AVR 4310 and it will boost the dB setting it figures out for the front channels so they match the rest of the system at that setting. Then whenever you want to use AV you just set the naim ppreamp volume at the same level. Once you have done that you can use the AV volume control for the system as usual.
The other possibility I have heard is to use some sort of ground isolation device at the coax cable end of your system. I don't have experience of these so someone else maybe help with more detail.
regards
Geoff
The harsh fact is that it is very easy to end up with earth loops where the signal has two seperate earthing points at the same time. This is most often due to the AV part of the system acheiving earth thru' your TV/Sat or cable 75ohm coax connection.
While unity gain is supposed to help it often doesn't fix this problem. I have found the best way is to cancel unity gain on the naim pre amp and always set volume when using the AV input to a fixed position such as 9.00 or 12.00. You then run the speaker volume setup on the AVR 4310 and it will boost the dB setting it figures out for the front channels so they match the rest of the system at that setting. Then whenever you want to use AV you just set the naim ppreamp volume at the same level. Once you have done that you can use the AV volume control for the system as usual.
The other possibility I have heard is to use some sort of ground isolation device at the coax cable end of your system. I don't have experience of these so someone else maybe help with more detail.
regards
Geoff
Posted on: 17 July 2010 by Richard Dane
Djorg,
is the noise still there even when no AV sources are connected to the AV2?
P.s. why have both the Denon and an AV2 in the system??
is the noise still there even when no AV sources are connected to the AV2?
P.s. why have both the Denon and an AV2 in the system??
Posted on: 17 July 2010 by IWC Doppel
I use an AV2 with a Naim 32.5 and I can have a high level of hiss if my bluray player is on standby at high film levels. I also fidn that moving between inputs there can be a high level of noise before it locks on using the Auto mode.
I have no problems at all when operating at very high levels for film and the scene is silent
I have no problems at all when operating at very high levels for film and the scene is silent
Posted on: 18 July 2010 by djorg
Geoff
Thank you for your advices
Richard
There are no noises (except the usual ones) with CD5x or Linn DS. It is only with the Denon and its 3m long RCA connect...
Richard, munch,
Oooops....I made an error here!
I do not have Naim AV2 in my system! I used the term AV2 to describe the Aux2 input if my 112x!
Thank you for your advices
Richard
There are no noises (except the usual ones) with CD5x or Linn DS. It is only with the Denon and its 3m long RCA connect...
Richard, munch,
Oooops....I made an error here!
I do not have Naim AV2 in my system! I used the term AV2 to describe the Aux2 input if my 112x!
Posted on: 08 August 2010 by Don Hooper
One way you can avoid earthing issues with AV kit is to do what I have done.
I only use optical connections for anything that has a floating earth. ie Blueray and Sky HD box.
Naim kit is NAC252/AV2/NAPV175/CBNAP250/NAT5/STAGELINE.
I do not get any hisses or hums from the system irrispective of the source used. All the floating earth stuff is isolated electrically.
Hope this helps
I only use optical connections for anything that has a floating earth. ie Blueray and Sky HD box.
Naim kit is NAC252/AV2/NAPV175/CBNAP250/NAT5/STAGELINE.
I do not get any hisses or hums from the system irrispective of the source used. All the floating earth stuff is isolated electrically.
Hope this helps