That used to happen to me with a Uniti I used to have not that exact message but something about temperature very, very annoying when you are in the middle of listening to something It never did stop so I moved it on.
I did have 4ohm speakers but had 5 meter lengths of Nac A5 and I also had a Unitiqute 2 which drove them perfectly well without issue.
so you got rid of it and replaced it? Or were you able to fix the issue, and if so, how did you do that? thanks.
It would be helpful to understand what speakers/cable is being used, as speakers also have circuit boards in them (crossovers), and both speakers/connections/terminals can change over time (e.g. even spooling up a speaker cable can have dramatic effects, as it changes capacitance of the overall circuit (IIRC)).
It’s also the case that driving ‘big’ or ‘demanding’ speakers with a relatively under-powered amp is likely to cause issues/damage, perhaps over time, than the other way round.
It could the Atom but it could be the general set-up - and more info is needed around this, if only to assist in mitigating the effects you’re experiencing.
The cables are Audio Quest type4 and are 4 feet or so long. the speakers are not big or demanding. They are B&W bookshelf speakers. This weekend, I am going to unplug and re plug the speakers. And then cross my fingers. otherwise, I will have to ship the unit back to Naim. it has been working flawlessly for 2 years. thanks for the reply.
Are your speaker cables in conventional, single wire configuration? No fancy biwiring going on, and links still in place between the 2 sets of terminals on the speakers. (I’m assuming there are two sets of terminals as most B&W speakers have them?) Naim amps generally work better with longer lenths of speaker cable in regular single wire configuration. Not normally too critical on an Atom as it could be on a separate Naim amp, but worth checking anyway.
OK & understood - but, in the world of hi-fi (and it is/was a trait of some B&W speakers), smaller size doesn’t mean easier to drive - strangely larger box speakers, although having more drive units, can be more efficient and easier to drive.
On the face of things, and I don’t think you are the first to encounter this (and there’s no guidance in the Quick Start Manual/Guide from what I can see), I suspect the combo of the speaker cable (not just type of cable but also length) & speakers isn’t an easy load for the Atom, especially where the volume is pushed a tad. Yes, it may have been OK for a long time but things do change.
I wish you well in resolving this.
FYI, have a look here to understand what Naim’s broader requirements & approach are re speaker cables/length etc,.
Richard, queries around speaker cabling seem to come up quite often for the Uniti-range products - and there doesn’t appear to be guidance on whether e.g. NACA5 is advocated/lengths etc, (not from the on-line QSG).
Can the Forum FAQ on this be updated, to at least give some direction on what to avoid with the Uniti range, as these products are targeted far differently than the Classic Range et al, where dealers may have more involvement?
not single wire configuration. The cables are Audio Quest type4 and are only 4 feet or so long. I am going to try all of these suggestions over the weekend and see where this leaves me. thanks so much.
very helpful! thanks!
HL, I guess that would be up to Naim. However, as far as I’m concerned (and I would guess also from Naim’s point of view), the basic recommendation from the FAQ stands for any Naim amplifier - use the supplied plugs at the Naim amp end, avoid any cable of high capacitance and low inductance, and if still in any doubt, go for NACA5 and you won’t be disappointed…
I’ve been using “Go 4” with my Nova and PMC Twenty5.21 for about 2.5 years now with no issues, though they are much longer than yours. The Go4 is basically the Type 4 with Audioquest’s little black box attached (Sorry, I cant remember what magic is claimed of it, but it sounded better than Type 4 on demo) so it’s doubtful that your cable is the issue.
As an aside, I did compare with NACA5 and both AQ cables sounded better to my ears. I had intended to but NACA5, but the dealer said “have a listen to this” and put Type 4 on - he just left me to play music - left me as in left the room - he did no talk up of the AQ or talk down of the Naim product. So I chose the AQ despite knowing I wanted the NACA5 when I walked in.
Do you mean that you are biwiring? In other words, do you have the links between the two sets of sockets on the speakers removed, with two pairs of banana plugs in each speaker?
oh man, i dont even know that that means! the only reason i knew what kind of cables they were was because i asked the gent who installed the system. But there are 4 connections to each speaker, if that is what you mean. Here is a photo.
I have a feeling this method of wiring (called bi-wiring) doesn’t suit the Atom and bi-wiring isn’t recommended for Naim’s amp’s.
Further questions, to get to the bottom of this:
1- How does the speaker cable attach to the Atom - I assume both blacks to black and reds to red?
2- Can you advise the precise model of the B&Ws … and are you aware if they’ve been modified in any way?
3- Have you link plates (or jumpers) which can be used to slide between the speaker terminals, so as to join and respective red & black terminals together (not red & black joined together of course).
4- Did an authorised Naim dealer install this?
See the guidance at the bottom of the Forum FAQ page:
Judging by his nick, I would guess 604, but which series?
Is it really bi-wiring if it’s the same terminals on the amp side, the atom only having one set?
I thought for bi-wiring you had to use different sets of terminals. This way the original jumper has effectively been replaced by the speaker wire, nothing more than that.
Hence the Q’s - as:
1- I know some legacy B&Ws are real current eaters
2- I’m not au fait with how B&W’s 4 speaker terminals work e.g. I assume whatever X-over is inside is bypassed?
The confusing bit to me is that (assuming the amp end only has 2 terminals, with 4 core cabling), is how the Atom is feeding the drivers - independently?
It seems the OP has a hybrid bi-wiring set-up - the Atom only has 2 pairs of speaker terminals.
I know bi-amping B&W’s was a solution for many, given how power hungry many legacy models were* - I think newer models are easier to drive.
*rumour has it B&W used large current pumping amps in their design workings at Worthing.
Hi all. Again, i am pretty ignorant of technical stuff. But let me do my best: 1) this one i dont know, but will get an answer. 2)I just looked at B&W website, and i think they are maybe 607s? they are small bookshelf speakers. 3)No idea. Will find out 4) yes, i have been buy from them for years, and they are the only authorized dealer in my vicinity. I’ll come back with proper answers. Thanks.
haha. No, 604 is the area code for Vancouver, Canada, which is where i live. also the name of my company. the rest of your note is way over my head! thanks.
i have an answer re speakers. B&W CM1 S2
All noted - thanks.
To explain a little:
An amplifier is like an engine, and the engine’s gearbox (output stage) provides power to whatever is connected to it. In hi-fi terms, this is a combination of the electrical qualities of both the cabling and speaker (and any joints in play).
I’m not sure what the electrical qualities of your AQ speaker cable are but it seems to be 4-core (2 red & 2 black), which are connected to the respective channels on the Atom i.e. each terminal at the Atom has 2 cables attached to it (that’s OK perhaps).
Now, the B&W’s appear to be quite demanding in efficiency terms (in converting electrical current in to sound level) - they appear to be rated at around 84db - although I see a review test suggested lower (~81db). This means the Atom has to work hard(er) to make them work which, in general terms, isn’t the best.
But (and here I think is the crux), the way the speaker is wired could be exacerbating issues.
When run in ‘passive’ mode, the rear speaker terminal pairs should have a gold plate between them, so an amplifier is driving in to both drive units at the same time. Inside the speaker is a crossover unit which splits the incoming signal to the drive units (tweeter high frequency and woofer/bass unit low frequency).
Intuitively, by splitting the AQ pairs and without the rear links, the Atom is being asked to drive the respective driver units separately (I will admit I don’t know if/how the speakers X-over network is them employed, or not). I suspect (and not knowing the electrical qualities of the cabling), as a relatively low-powered amp (in the world of amps it is), the Atom often really struggles with the current demand which it is ‘seeing’.
When I say ‘seeing’, this is also a reflection of the efficiency and specs of the speaker. The B&Ws, as well as being inefficient (in relative terms), are rated at 8ohms resistance (nominal) but reviewers note this can dip down to close to 2 ohms.
This latter trait is nasty for amps. An analogy is like driving on a road when you encounter ice, the engine revs increase suddenly as the rolling resistance from the road reduces and the tyres lose traction - a side effect can be that the engine can over-rev and it becomes less responsive, and the amp’s grip & control of the speaker cones is compromised. And if you play music loud-ish, the amp can really struggle. It’s working its heart out just trying to keep up and the rev-range (headroom) of the amp is grossly diminished - the usual sign is that the amp runs hot.
I wonder if the way it is currently wired, the resistance of the speakers is reduced as the drive units are (in concept) being run in parallel.
Suggestion:
If you have the gold link plates, re-install them and wire up to only one set of rear terminals on each speaker - you may be able to get away with splitting top & bottom (as it looks now). The key thing is that the speakers’ cross-overs are fully engaged.
FYI, the rule with amps & speakers is to have a far higher rated/better quality amp driving in to more modest quality speakers - a bit like the car analogy, the bigger the amp engine, the lazier it can work and when the music peaks come, it has the power to handle the signal needs and the traits of the speakers.
In the land of hi-fi, damage can be done to amps & speakers if, for example, a lower quality amp is asked to drive a set of demanding speakers as:
1- the amp may be being asked to operate > its performance envelope - shut-down (over-current) protections are often there to protect this from happening.
2- the signal the amp feeds to the speakers could, in extremis, be > the operating envelope of the speakers and could blow-up a drive unit/even damage a cross-over.