I can’t say I’ve ever heard of length of cable being an issue for preamps, including Naim’s though only someone from Naim could be definitive about that. Speaker cable length with some of Naim’s power amp is another matter, though usually it is not wanting them too short. However with unbalanced low-level signal cables, such as RCA interconnects, long cable lengtgs can be prone to hum pick up – perhaps this is what you has heard about? How long a length before it becomes a problem would depend on the electromagnetic environment through which the cable passes (primarily proximity of mains cabling & transformers) and the quality of the interconnects’ screening. Balanced cables are immune, so better for longer runs, but only if the preamp has suitable outputs, otherwise requiring a converter (typically special signal transformers).
I seem to recall mention of this issue in regard to using active ATC speakers when the speaker are a reasonable distance from the preamp, from memory short cables runs were okay but as the need for longer lengths arises there can be issues.
Tried to find the thread at the moment but l’m sure there was mention of a transformer or something similar.
I run 7M lengths of XLR to ATC actives with no issues. From what I’ve read anything up to 30M is fine, also other views that beyond this is OK, should cover most domestic situations.
I’m sure that whatever you’ve seen will be as I just detailed.
You can get special RCA plugs with a “balun” (balanced to unbalanced - and vice versa) transformer built in, for wiring with balanced cable, or a short balun adapter link to use with standard balanced cable. (At the active speaker end they just plug directly into the balanced XLR input.) Good quality balanced cables need not be expensive at all - I imagine if asked either PMC or ATC would confirm those from the likes of Mogami are eminently suited.
Appreciate that, sometimes you pick up on something and get the wrong end of the stick so to speak, things are much clearer now, many thanks.
I think some preamps can have issues with long rca cables. I’m not sure that includes OC Naim preamps and I doubt it, but probably worth checking with dealer or Naim first, I’d have thought. As IB says above, experimenting with an unbalanced to balanced transformer may be worthwhile.
NC Naim preamps and Atom HE have balanced XLR outputs and balanced cables of any length likely to be used in a domestic setting should be fine.
Roger
I have Mogami XLR with my 40A… even if I find them good I bought to try Wireworld Eclipse 8… the difference is big in favor of WW, there is no doubt possible.
Only if you drive them with a passive preamp, you need to consider the cable length. Otherwise it shouldn’t be a problem.
Type of preamp is irrelevant. It is the gain of the power amp at the end of a single-ended (i.e. unbalanced) cable that is the main factor, and that does not change with preamp.
I’m not good with the technical explanations but I do remember reading that you should keep the downstream cable length short when using a passive preamp. This was mentioned in some GoldenSound review, where he compared passive and active preamp (I couldn’t find it now). But quick googling supports this.
For example:
”Passive preamps benefit from shorter and/or lower capacitance interconnect cables between the preamp and the amp. But don’t get too worried about this. Just try to keep downstream interconnects to 6 feet or less. Upstream cable length doesn’t matter.”
If that’s the case then possbiblt an impedance matter. But as said, even with powered preamps long unbalanced cables may alliw hum pickup. But how long is “long” depends on various factors
Hi @silverback
Sorry to miss all the fun. It’s been a busy day and just catching up now …
Here is a late answer to your question. Which others have more than covered for you.
The cable you ask about is indeed for connecting OC Naim onwards to active speakers.
In our use case, ( would be same for you too ), the connection is made from external psu - a HiCap DR - on 4 pin DIN connectors, using the DIN connectors on the rear side, any of three sockets no1, no2 or no3. Two separate cables are used, one for left channel, second for right channel. Speaker end is usually XLR or sometimes RCA. Depending on active speaker.
Yes, think of this as an audio interconnect from Naim pre-amplifier controller - onwards - to power amplifier in an active speaker system.
Currently using those same cables at home - HiCap DR to each PMC as active - think that are maybe 4m long each. Works well and zero problems with this.
Although not that common in the HiFi market , ( one end as 4 pin DIN just for Naim OC items) they are easy to make or buy. A dealer can usually sort this for you. There is lots of discussion on this topic in the “Show us your ATC’s” thread.
So, it looks like others have touched on differences between balanced and unbalanced audio interconnect cables. Maybe do some reading on this topic.
Also, look at quasi or pseudo balanced.
NC is now different…
NSC222 and NAC332 have balanced outputs on XLR.
Suppose this is an innovation for Naim really and allows for better integration into other audio products and systems. It’s ideal for connecting onto active style speakers, also with balanced connection using XLR, ( such as all ATC active models and also the new PMC active module too ).
Balanced XLR to XLR is a very common interconnect. Mostly pro audio market. Some consumer HiFi market too. Lots of options to browse and buy.
With balanced audio cables, the length is not really an issue.
As any noise induced in to the signal cable is cancelled out.
Balanced lines are quieter and specifically over longer lengths. That’s what it’s all about.
Unbalanced lines are still okay, up to a point ( length ).
Hope that helps.
Best wishes
R
Listened to the limited edition stand-mount SCM20 ASL fed by dCS Rossini Apex at my dealer yesterday.
Beautiful to look at and a simple set up that produced effortless, flowing and natural/realistic music – a v nice introduction to active speakers.
My only gripe was I can understand why ATC offer a matching subwoofer.
Sure
They look really attractive in the High Gloss Blue Lacquer finish.
Suspect they might sound a bit like the active 20 towers, we had on loan at home a few weeks ago.
Thanks for posting those thoughts
R
Spec sheets are the same so would not expect much difference if any but I’ve not listened to towers.
Don’t get me wrong they were very impressive.
For me actives and streaming pre-amps, I don’t know whether you’d call them lifestyle products, appear a viable alternative to Naim amplification for digital source users. Clearly still room and personal taste dependent!
Given the home demos you’ve done, have you measured with REW or similar?
Sure. Agreed.
Would be intriguing to understand what difference the tower cabinet makes ?
No
I’m wishing I’d maybe done that 
So, relying on my old cloth ears for now.
IMHO, was astonished, impressed with what the active 20 towers did with LF. Suspect they go much lower than as stated in their spec’ sheet. I think they do. Maybe ATC are being conservative with what they publish.
Another forum member - explained above - to distinguish between control and grip, from just low low notes, per se.
Anyway, they made a really positive impression on us during the home loan.
Think the active 20 towers as a really good execution of what active speakers can do…
BW
R
With you coming from ProAc D20R, think I understand that comment.
Have heard those speakers recently - along our own journey - and thought them a viable option. Very capable speaker, nicely balanced. Liked the ribbon tweeter too. Particularly liked they way they deal with LF, ported through bottom of cabinet etc. They reach low in a satisfying way. Think they are a relative bargain at their price.
Happy Sunday listening
R
Surely that should only be a gripe if they didn’t! For ATC to recognise the bass limitation of a small speaker and offer a solution that presumably would integrate well, rather than pretending the speaker can do everything, seems commendable to me!
Indeed, let me be clear the stand-mounts were terrific - and made a very convincing argument for ownership.
Potential room gain and other interactions, in your listening space, is something I’m unaware of but you will just know/be familiar with hence the question about measurements.
I was at the dealers to listen to some LS50 wireless ii active speakers for a “cheap” second system but we really didn’t get on…… so I’m back to the drawing board!
Interested to see where you land although I think we know where you are leaning and with good reason.