Mains causing channel imbalance?

I have a persistent channel imbalance issue, system is a ND5Xs2 initially into a Supernait 3, I always felt the sound was constrained within the bounds of the speakers and the sound stage pulled to the left slightly , this was consistent through a change of speakers and addition of Hicap DR and a NaC 282 fronting the SN3. Everything sounded centrally balanced through the headphones so I thought maybe it was the power amp Section of the SN3 causing this, upgraded to a 250 DR so the SN3 no longer being used and the channel imbalance is still there but reversed now pulling to the right. Playing about one evening I reconnected the bare SN3 back in but powered from a socket the other side of the room and no channel imbalance was evident. So think it could be a mains issue, I don’t have dedicated mains but use a Wireworld Matrix power block and wonder whether that could be the culprit? I also have a Nait50 and have no such issues, plugged directly into the same double wall socket as the Matrix Block which powers the ND5XS2, the Nait is fabulous and I would say beats the 282 250 combo so something cant be right. Anyone else experienced anything similar?

Don’t confuse fause with correlation. You changed sockets and the problem went away. But not because you changed sockets. While the problem might be perplexing, mains can’t cause this problem.

You may have to look very carefully at other factors that changed such as nudging interconnects when reaching round the back etc.

[addendum] I take that back. Can you use a mains tester ($20 on Amazon) and confirm that the problem socket has 0v over ground? Mains earth to signal earth pollution could cause signal lift.I’ve seen 7v over earth before. However, both channels ground to the same point so I still suspect mains is not the issue. But curiosity would make me test it anyway.

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I am not aware of any mechanism that would allow mains supply to cause a channel imbalance. I would say it’s highly unlikely - but I wouldn’t like to say it’s absolutely impossible either!

A few ideas. Sometimes channel balance can alter with volume setting, depending on the accuracy of the volume pot used. Typically at lower volumes, ie. lower positions on the volume pot, channel imbalance can sometimes occur.

Sometimes, depending on the position of the speakers, the illusion of a channel imbalance can occur. For instance, if one speaker is postioned so that it produces slightly more bass than the other, then the sound can seem to pull towards that speaker. Or room reflections can create the same sort of illusion.

My guess is that changing the mains socket produced a slightly different tonal balance and the illusion went away.

Try physically swapping over the L and R speakers. If the imbalance is also swapped over it implies that the speakers are mis-matched somehow. If not, then try swapping over the L and R speaker leads. If the imbalance is also swapped it implies an imbalance in the amp or further up the chain.

If neither of these things has any effect then I think you need to be looking at room created effects.

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I can’t think of any mechanism by which the mains could in any way cause channel imbalance.

You say it stopped after plugging into a different socket. Have you tried the very simple test of plugging back where it was? Only if it is repeatable, happening each time you swap with consistent imbalance in one socket and not in the other, would I even start to wonder about the cause being associated with that. There are many potential causes of imbalance other than mains, and one of the other possible explanations for the change as suggested by FZ seems far more likely. When there is imbalance investigations such as suggested by PJL could be worth doing.

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I had a similar problem to this but it was caused by a dodgy speaker cable. A couple of broken strands and a dry joint.

I did wonder whether it could be speaker cable so had a well respected trade member on this site re do the plugs on my NACA 5. It did help a little but the problem is still there. What I find strange is that with my Nait5 there is no issue, and that when I added the 250 the channel imbalance reversed. And it has been the same with 2 pairs of speakers and cables. Think
I will first buy a mains tester, if that does not reveal anything then unplug and re plug all the interconnects, it’s just such a faff getting to the back of the rack . Or maybe just keep the Nait50, it really is a special little amp!

What kind of mains tester? What parameters will tell you anything of relevance to channel balance? (Clue: none.)

You’ve identified changes when swapping amps, and with changing other connections. For starters I would do a systematic assessment of cables and their connection - swapping between channels, one linkage at a time. But first, are you consistently using the same tracks? And sitting in precisely the same position (have you played with varying your position?)

I think the same thing but keeping an open mind, it would be good to ensure there is no voltage over ground above 0.5v (or whatever the standard permits in the OPs country).

Bearing in mind Naim common signal ground to mains earth and the fact I have very recently seen (and had fixed) an issue with 7v over mains earth, I think it’s worth checking. I agree it’s extremely unlikely to be mains. But I’m unsure how an amp would react if there were issues such as ground and neutral reversed or voltage over earth. After all, post rectification it’s DC which to me only leaves ground anomolies.

Thanks. My feeling is that I should check the mains first, then the interconnects ( I know the source is fine as there are no issues through the Nait) . Speaker cable has recently been re terminated in an attempt to solve the issue so it’s not that , also tried another speaker cable but the imbalance remained. Maybe the 282 needs a service HiCap and 250 I have had from new but 282 was secondhand about 10 years old I think. The thing I find strange is that the issue has been present through bare SN3 and each stage of upgrading through to what I have now. I may also try relocating the system to the other side of the room so I can get the whole system plugged into the other socket.

You’ll want something like this. Dirt cheap.

I use one ob every socket when I move into a place or a sparky does work. I’m their worst nightmare. Last one found a long list of issues over about 80 sockets.

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Thanks that’s the exact one I was looking at

It seems unlikely, but how about swapping around the actual mains leads…?

I will try that and also going to try a different mains block in place of the Wireworld Matrix to see if that makes any difference.

This is in no way a mains related issue.
You have to look elsewhere interconnects etc and the balance on the amp in case of needing calibration.
Don’t waste your time and money throwing things at the mains. :face_with_hand_over_mouth:

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