NAC202 NAP200 hissing & humming

Hi all,

I am aware that this topic came up before. Unfortunately I couldn’t find a solution so far.

Recently I bought a preowned Naim combination consisting of. NAC202, NAP200, HiCap, NAPSC clone. All components from around 2009 in perfect optical condition.
Amplifier combo plays together with ND5XS2 and B&W 702S2.

The combo plays very well, but without signal there is an audible humming coming from all transistor containing units, but the ND5.

Secondly after starting up the system, again without signal, I get a hissing from the tweeters, which is independent from the output volume on the preamp.

To tackle the humming, I already tested a DC blocker from HMS to no avail.

What I didn’t test is to run the system without the upgrades, because I don’t have the link plug.
As far as I know this link plug bridges 2 of the 4 contacts. Can anyone tell me which contacts, so I could test with a wire?

Has anyone had the same issue?
What is the source of the hissing NAC or NAP?
Any tipps what else to test or how to solve the issues?

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Hissing on Naim kit whilst idle is normal. It shouldn’t be audible from your listening seat.

If you have been supplied with both link plugs on the 202 you could remove the HiCap and whatever you are using for the NAPSC. The 202 would then be powered from the 200 and this would eliminate any external supplies.

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The OP says they don’t have these.

Recommend the OP contacts the Seller who ‘should’ have them… :thinking:

Failing that, the Link Plug(s) can be bought on line, from I think, TomTom.

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I missed that paragraph :face_with_hand_over_mouth:

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I would buy two more link plugs and test 202/200 alone.

Paddle on link 1 and little round 5 pin job on link 2 is the way I remember it from when I owned a 202. Whether they are both called link plugs though is obviously up for debate!

But both would be better than messing around with bits of wire on, what, roughly five and a half grands worth of amps at today’s prices.

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Do you know when they were last serviced?

DG…

I had that setup. and it worked without issue, although I was using an UN Naimed power supply.
You should be able to get a spare link plug from your local Naim dealer, or a popular auction site.

Thanks for the hints.

Cables are all genuine.
And yes I will get a link plug and test, before risking a damage. Couldn’t find it online.
So far no service as far as I know, which should not be an issue for 13 year old amp.

I found that my AUX2/Stageline input was affected by USB / Ethernet noise, although it was minimal. No other input had this issue.

At 90dB/W at 1m the B£W 202S2 is a little higher in sensitivity than many, so the hiss will be louder, but how audible at the listening position will also depend on distance.

The classics i.e. all of yours should ideally be serviced every 12 to 15 years. Right about now would be ideal.

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It would be extraordinary if it didn’t :thinking:

My point of course following on from noting that the OP’s speakers being more sensitive than most and so would more likely to be audible at the listening seat, was that would be all the more likely if they sit closer than most.