NAP100 loud buzz

I recently purchased a used NAP100 to use with a Unitiqute 2 and although there is no problem with sound quality, there is a very discernible buzz from the casing. I have read other people saying the same thing with Naim power amps and the answers about disconnecting various cables to find which causes the problem and have done so but the buzzing remains. Are the amps easy to open up so I can check for anything possibly loose or obvious? (with power off of course!)

If the buzzing is coming from the case rather than from the loudspeakers, then you have two possibilities. One is a faulty transformer and the other more likely one is that your mains has a dc offset caused by something else connected to it.

The normal advice is to turn off everything else in the house so only the NAP100 is on and then assuming it’s now silent, gradually turn things on again until you hear the buzz. The last thing you turned on is the culprit.

If everything is off except the NAP100 and you still get the buzz from the case then the fault with your mains probably lies outside your property. You could take it to friend’s house (not one too close to your house) and see if it buzzes there too.

Best

David

Hi David,

Thanks for the advice, there are a few items connected close to it so when I get the chance I will disconnect everything as suggested and take it from there. I wonder if it may be something to do with the extension lead it is all hooked up to? I never had any issues with my previous amp and nothing from the Qute either. It is not possible to do away with the extension lead as the audio equipment is too far from the sockets to plug in direct to the wall sockets. Don’t really want to start complicating things with mains conditioners and the like as the whole idea of the Unitiqute was to lower the box count in the first place.

I don’t think an extension lead is likely to cause this. More likely is a fridge, or a central heating pump, or heater/fan/air conditioning unit. Hair dryers and hair straighteners are often mentioned.

Also it may be a fault, which is why I suggest trying it somewhere right away from your home. You don’t need to connect it up. Just plug in the mains lead and turn it on. Does it hum/buzz like at home?

Best

David

I will at first opportunity remove it and try it at another abode, unfortunately I don’t think I will be too popular if I have to throw the fridge freezer away or turn the heating to off :face_with_head_bandage:
By the way, this little set up with my Proac Ref8 signatures and a Rel sub sounds mightily impressive, I kept my old amp and CD player just in case it disappointed, they are both boxed and in the loft now.

If the noise never varies, it has to be caused by an appliance that is permanently on, in which case it’s not going to be a fridge or a hairdryer. It’s more likely to be something on your incoming mains supply, which you probably can’t do anything about.
Not all Naim boxes are equally affected either, so you will have to decide whether this level of hum is acceptable and just live with it, or whether to try a different amp.

It does depend on the fridge! Certainly the compressor turns itself on and off but I have one fridge where a circulating fan runs 24/7 and another fridge/freezer where the fan is only off when you open the door.

But basically I agree with you Chris.

Best

David

I am not sure it is an acceptable level of noise, don’t notice it while listening to music but it can be quite annoying at other times so may need to make sure it is not a problem with the amp and move it on. I will take it to a friends house and try it there.

It may well be perfectly fine, Transformers hum, it is in their nature. Every Naim transformer I have hums, each at different levels. Do I hear it when I walk by the system, sure, do I hear it when listening to music, no.

Thanks for the input, it certainly sounds fine when listening to music so I doubt it is faulty but not sure that makes it acceptable, I have owned some fine amps over the years and none have made anything more than a very very faint noise. I will on previous advice take it to a friends home to plug it in and see if there is any audible difference.