SuperUniti B&W PM1 issues

Hi Everyone,

First post here, so sorry if this isn’t the right thing in the right place, but here goes…

I currently have a SuperUniti with B&W PM1s. It’s a system I’ve had since 2013.

The truth is I’ve never been really happy with it. It just doesn’t seem to have the life and energy that my old Rega Planar 3 / A&R A60 / Heybrook HB2 system used to have. It feels, tight, small and congested.

I don’t have a huge budget to fix the problem, so I don’t want to throw the baby out with the bathwater. Both the SU and the PM1s were highly regarded, so I can only assume that either there is something wrong, or it’s an unhappy combination, or the combination doesn’t suit my room, which is probably about 11m x 5m, with the speakers firing across the middle on the long side.

It could even be something that is connected up incorrectly - but I’ve had a pretty good check and I’m fairly confident it isn’t that (out of phase or something silly).

I know it’s very hard for anyone to be sure what the issue might be without hearing it for themselves, but it would be very useful to hear from anyone who has got or had experience of the SU / PM1 combination? Or any Naim / PM1 combos for that matter?

Thanks very much!


Which speaker cables are you using? Also does the system come to life as you crank the volume? It’s been a while since I owned b&w but mine were a bit lifeless at lower volumes.

When I had an SU I used it with PMC twenty.23s and it was very good. I’d suspect it’s the speakers that are the issue. You might want to try alternatives, but that’s hard at the moment of course.

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Hi Robert,

That’s an interesting point - I’ve tried three different cables so far, the most recent were supplied by a Naim dealer who recommended some fairly basic, but thick simple copper cables, which (even though they were cheaper than the fancy silver shielded cable that I was using before) gave the best results so far - but still not great. I must admit I haven’t tried NAC5 because I’m worried about it’s lack of ability to go around corners. Do you think it is likely to make a real difference? Perhaps I should borrow as set of NAC5 to make sure that isn’t the issue.

Also, in some ways, the speakers do sound better as the volume goes up - but at the same time they can start to sound congested. It kind of sounds constrained - the opposite of effortless, if you know what I mean. It encourages you to turn the sound down - which I don’t think is a great sign!

The whole system sounds OK with simple music, but complex rock music played hard just doesn’t sound nice.

Thanks Hungryhalibut - Yes, I’m beginning to suspect the same. Useful to know you were happy with the SU with PMC twenty.23s. As you say, I’ll try some alternatives, once we get out of the current tricky situation.

I did have one Naim specialist suggest to me that the SU doesn’t actually have enough grunt for the PM1s - which surprised me. He said the PM1s were actually quite a tricky load and really need something like a 250DR to make them sing.

Move them further away from the wall, that could well cure the congestion. I do understand that this might not be feasible as a permanent solution, but it can be a good test to see if the congestion gets less.

Also, what happens when you ‘fire’ them in the lengthy direction of the room?

Btw, I have 3 years experience trying to make the best out of CM1’s & CM5’s in a similar sized room as you have. I ended up with SBL’s :slight_smile: this cured everything. PM1’s are still on my list though, I think they are fabulous loudspeakers.

I could make the B&W’s work (very) well, but they had to be positioned in the walking path which simply made it impossible in our current busy family / living room layout.

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Naca5 is well worth trying and I think is the default to use with any Naim system. You should be able to borrow a set from your dealer. Ideal length is 3.5m pair. They are stiff and resist attempts to bend, but can be tamed by warming up with a hair dryer, bend then allow to cool, if needed.
There are many many speakers out there probably too many to try but some possible alternatives for you would include kef ls50, neat ministra and aforementioned pmc.

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Thanks Robert - yes, that’s wise, I’ll try and borrow a set of NACA5 cables.

I had wondered about LS50s too.

OK, thanks, that’s very interesting. I’ll try some experiments to positioning of the PM1s.

I would try naca5 speaker cables

Is the SU directly connected to a wall socket ?

Are there any maybe mains extensions at home with surge protection ? They need to be turned off or replaced

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Thanks for reply, all these thoughts are helpful. SU is plugged directly into wall socket, although I’m not convinced our house has the best mains wiring. There is a gang extension plugged into the twin wall socket. I’ll try disconnecting that. I will also try and borrow some NACA5.

Thank you.

please confirm the grounding switch on the SU is set on “chassis”

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You may have a bit of a mismatch as your speakers are quite difficult to drive with a sensitivity of 84db.
I think you would have to either get a more powerful amp or speakers which are an easier load on the SU.

OK, so I checked the grounding switch on the back of the SU and it was set on “chassis”, however, I toggled between “chassis” and “floating” and back again, just to be sure. I then unplugged the gang extension plug that was plugged into the twin wall socket that the SU was plugged into. (The SU was plugged directly into the wall socket, but the second outlet of the wall socket was feeding an extension cable).

Then I listened, if I’m honest, not really expecting to hear any difference…

I was wrong! The SU seems to have come to life, with far more energy and bass.

Arguably the speakers are too small for the room and / or too tricky a load for the SU - but to be honest, right now I think it sounds pretty damn good. So thank you!

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Hi Analogmusic,

I just want to say thank you - to everyone, but especially to you because I think you might have solved the issue! I’ve spent quite a few hours listening since I removed an extension bank that was plugged in next to the SU’s wall socket - and the difference really is astonishing.

It feels as though the SU has always been strangled and suddenly it’s been released. Not sure I really understand the physics behind what was going on before, but clearly something wasn’t right.

Sounds amazing now - so thank you!


What a great result, and well done @Analogmusic. I would never have thought of that.


As a matter of interest what did you have plugged into the extension block//lead that you removed, and was it protected with any kind of overload/mains filter or did it have a neon lamp?

Hi Chris,

The extension block was powering a lamp, a Panasonic DVD Player/Recorder and a Denon CD Player. The extension block itself did have a small red light on it, which I had noticed was flickering - which didn’t seem right to me.

I have now unplugged the extension altogether. The lamp is plugged directly into the wall and I’ve powered the DVD Player/Recorder from a socket on the other side of the room and the CD player is off.

The SuperUniti is massively better as a result. This isn’t a small change - it feels like a different machine.

I should say that I did toggle the ground switch on the back of the SU at the same time as I removed the extension cable, although I simply switched from chassis to floating and then back again just to make sure it was in the correct position. I don’t think that was the issue, but as I did both things at the same time, I can’t be 100% sure, and I don’t really want to touch anything again, just incase I upset things!

7 years late, I feel like I’ve finally joined the Naim club!