I’ve read multiple times that the Qutest induces humming when connected to Naim amps if the qutest is not properly grounded. Does this always happen, or is a bit of a lottery?
Never heard that before, mine is dead silent.
My understanding, probably incorrect, is that grounding is not an issue on products that have an external PSU, like the Qutest.
Items that have onboard PSUs are either grounded or double insulated with no ground. It is these latter items that are most likely to cause ground hum issues, the Bluesound Node is a perfect example.
Happy to be totally shot down and corrected.
When I had a Qutest is was perfectly quiet running into the XS3 I owned at the time.
From what I understand and I could definitely be wrong it sometimes happens if the qutest is connected to a Naim streamer. I think it can depend which power supply you use with the qutest. Regardless it’s a relatively easy fix according to other forum threads as it can be grounded with a piece of wire
Possibly a grounding issue as already mentioned. Check that you have one grounded source, ideally connected by DIN cable to your Naim amp, and check that the grounding switches on the rear panel of the Naim boxes are correctly set. This, however, would address humming from the Naim system, not from the Qutest.
Another possible issue is the proximity of the switching power supply for the Qutest to the Naim boxes. Ideally these should be kept apart, not on the same wall socket or mains block, and if possible, not even on the same mains circuit.
It’s quite possible that none of this will cause you any problems, but if it does, these are the first places I would look.
Never had a hum. Two Qutests on variousNaim kit over the past few years.
No. But it’s likely if the signal ground is not connected to safety earth, ideally in one source component only. In the Naim ecosystem, that would normally be the cd player - which is why (all?) other Naim source components have a ground switch on the back panel.
I have a Qutest. No issues, although I’m not using it with Naim gear.
If the Qutest is being used with its supplied PSU, which is a requirement within the terms of warranty, then it will not be grounded as the supplied SMPS has no earth connection. So the simple answer is that you can’t ground the Qutest without using a PSU that is grounded and thus voiding your warranty.
I don’t think the Qutest would generate any hum either in itself or via the supplied SMPS under any circumstances if working correctly. Humming suggests that there is a fault somewhere.
Loaned a Qutest when my TT2 was in for repair and there was nothing. TT2 is about to go back a second time so I may end up asking nicely for a Qutest again. Will report back if I do and there’s anything different.
If you have no other grounded source into your amp, this may be the problem. The grounding cable as described here fixed the problem for me.
Thank you for your replies. The only source connected to my 282 will be the Qutest (fed by nd5xs2) using RCA (my dealer is lending me his Qutest for a few days).
Mine hummed with a SN3 until I put a linear supply on it… but I did the link wire mod before I hit the mcru supply
No hum here. I’m using MCRU linear ps now but used the standard supply for years with no hum issues at all.
If you do this, try connecting the DIN cable supplied with the ND5XS2 to the 282. It won’t be carrying a signal, of course, but it helps to maintain the correct system grounding which is otherwise lost with an ungrounded piece of equipment like the Qutest.
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