Low hum even when source disconnected

Hi All
I’m getting a low hum from my amp itself and the speakers.
Firstly, the amp hum is very low volume and doesn’t seem to be affected by turning the volume dial up it down
Secondly, the speaker hum is slightly more noticeable even at a quarter turn and becomes very clearly noticeable at full volume.
Note, as per the thread header, this is the case even without a source connected.
It’s a NAC122x/NAP150x amp.
Is this normal? Is there anything I can do to minimise it? If more information is needed, ask away.

Yes, exactly

Hi badyogi,
I have been there too.
I had a silent running 122x/150x combo for a number of years. All my kit was very well looked after, but the Amp eventually developed a low hum that also became slightly audible through the speakers. It was suggested it may have been a noisy transformer in the amp. Your description sounds very similar to the one I had, so maybe it is a common issue. The 150x was in production between 2004 and 2009, so not that old really, but might gain from a service.
Personally, I would check with your local Naim dealer for advice first or contact Naim customer service to see what they have to say.
Incidentally, what speakers have you paired with your 150x

Good luck,

So you are getting hum from the amplifier itself and from the speakers, with nothing connected to the power amp except the mains and the speakers?

If so then for sure your power amp needs a service and personally I wouldn’t be using it until that’s been done. (It sounds like catastrophically failing power supply capacitor(s) to me.)



Thanks for your replies. I suspected it might need a service as it’s 11 years old now. I hope it will see me through the lockdown!!

fingers crossed it will

I’m expecting it back from Darren at Class A tomorrow. When the speakers popped and the lights flickered I thought I’d better get it serviced!!

Can’t wait to hear it



Great stuff, hope it sounds like new :slight_smile:

Got the serviced NAP150x back from Darran at Class A. No hum and it sounds awesome. Furthermore, I’m told it will only get better over the next few weeks. No need to splurge on new speakers or a sub just yet! Although I’m tempted to add a hicap of some variety too the NAC122x.

Thanks all, especially Darran.

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