Help please!
An engineer 'friend' fixed a connection problem with my NAC and kindly 'levelled' the inputs for me while he had it open.
As a result I now have the same sensitivity on both DIN and RCA (aux) inputs which makes it unusable for me as:
- my Magik DS can hardly be heard even on full volume
- my Meridian CD player (2V class A according to the manual) is way overloading all the inputs. It normally plays fins through the AuX/RCA
The only info I can find online is that the NAC DIN tape inputs should be set for 75mV at 100kOhm.
I'm guessing he's set all inputs to somewhere between 75mV and 2V, which is too insensitive for the Magik and too sensitive for the Meridian.
Can anyone confirm what they should be, or otherwise help me get it straight again.
Many thanks, Chris.
Posted on: 20 November 2018 by Richard Dane
Chris, it's impossible to know exactly what your "friend" has done here. Normally a CD player at 2V should be nowhere near overloading the inputs - they can take 7V. However, do make sure you aren't playing into an input with Phono boards first! I would suggest you take the NAC32.5 to a Naim dealer so it can be inspected. Then, if needed they can send it to Naim so any of your friend's work is undone and rectified and then the unit given a proper service. Alternatively you could approach an approved Naim service agent such as Class A, who may work out a bit cheaper cost-wise. I would give Darran at Class A a call first and explain what has happened and take it from there.
Posted on: 20 November 2018 by Richard Dane
Chris, yes, 7V output would make the volume pot pretty much unusable, however, the inputs are designed to take 7V before overload.
Posted on: 20 November 2018 by ccfpcl2
I've taken it back and he's cranked the preset pot on the aux board right down. It's still pretty loud with my Magik going into it, but I now have about 1/3 turn of usable range, so I guess that will have to do.
Thanks all for your prompt advice.
Posted on: 20 November 2018 by Richard Dane
Ah, it sounds like you have got NA328 boards fitted on the AUX input. These shouldn't really be used these days as they have not just a variable attenuation pot onboard but also they mess with the FR. They were designed to try to make early CD players sound a bit more acceptable but results were somewhat equivocal. For modern digital sources they are best removed and replaced with NA326 link boards, or use one of the line level Din inputs
However, I'm not sure why your Meridian player is overloading all the inputs. This would suggest that something has been done to the main board.
