Oh, and one can also use ‘regular’ banana plugs, however Naim amps require some inductance and capacitance when it comes to speaker cables. Not sure if the Kimber is a good match, but sure many others might chime in …
Kimber is the cable brand that one can usually rely on being unsuitable for Naim amps. It’s braided and has all the wrong specs. Though kudos to them for publishing specs.
This is the Monocle X:
(Cp) parallel capacitance: 315.6 pF / meter
(Ls) series inductance: 0.3784 uH / meter
I.e., very high capacitance and low inductance.
This is what Naim amps want (from the forum’s speaker cable FAQ):
you should ensure that the cable is low capacitance and of moderate inductance.
High capacitance &/or very low inductance cables are to be avoided at all costs and may result in damage to your amplifier.NACA5 specifications are as follows:
Capacitance: 16pF per metre
Resistance: 9 milliohms per metre
Inductance: 1uH per metre
The minimum recommended length of NACA5 is 3.5 meters. To reach the same inductance, you would need 10 meters of the Kimber cable, which puts the capacitance value into a wholly different magnitude, compared to the recommendation. I wouldn’t be surprised if the 250 overheats and shuts down with such a cable
See:
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Blimey! I’m glad I asked the question then. I also have some Nordost SPM cable (3m lengths). The Kimber is 16’ lengths. Would the Nordost be ok?
My NAP250.2 really didn’t like it when I tried my kimber 8TC on it. It really didn’t sound good snd the amp soon got hot, so I quickly disconnected. I knew it wasn’t suitable but curiosity and all that…
Thanks all, just checked and the Nordost SPM is 2 x 2.5m. Has anyone any experience of using this? What cable are other people using with the 272 / 250DR combination?
Not really. I can’t find them on the Nordost website but found a review online stating:
capacitance (6 pF/foot) and inductance (0.07 µH/foot)
So in meters that’s 19.8 pF/meter capacitance, which is OK, but 0.231 µH/meter inductance, which is very low. You can reach the minimum recommended inductance of 3.5 µH by using 15.5 meters, which gives you 3.58 µH. This gives you a capacitance of 306.9 pF, which is just about inside the recommended envelope.
However, the minimum inductance is the more important value, and at about 1,000 pounds per meter pair for this cable, I doubt you want to use 15 meters of this 
At 2.5 meters you would reach 0.58 µH inductance, which is about 1/6 of the recommendation.
All braided and litz type cables (typically Kimber, Cardas, apparently at least many Nordost, others) are typically the opposite of what Naim amps want.
I’m using NACA5 and it sounds perfect as it should.
Are Naim suggesting Naim cables? Am I being cynical in thinking they would do that wouldn’t they…? Incidentally, I’m not doubting what you’ve said and I appreciate you taking the time to do the math.
They are mainly recommending that the cable has the specs that were assumed by the amp design, such as a minimum inductance (there’s a simple reason in the electrical design, see the FAQ link I posted earlier). And they publish these specs, so others are free to develop suitable cables. It’s on the cable brands if they don’t.
Sure, if using Naim cables you can be sure that they fit. Just like with interconnects, this is something many Naim customers cherish, to get cables (interconnects even in the box) that are designed for Naim and work, instead of buying them from third parties. And why not, surely anyone buying Naim gear has a fundamental trust that they know what they are doing - why would they not know which cables fit into the Naim sound. However, Naim are not getting rich from NACA5, which is a fine speaker cable - something that cannot be said about certain other brands like Nordost who are selling cables at a going rate of 1 firstborn per meter. (And at this price you can get Naim’s SuperLumina if so inclined).
It’s mainly about not being braided and of litz type, and with a bit of distance between the plus and minus conductors - if a cable construction resembles NACA5, it is typically fine. Some brands like Kimber and Nordost simply choose to design their cables in the opposite way - that’s fine and they may work with amps of other designs, but it’s not for Naim amps. They may have suitable cables as well, but check the specs. It’s a real issue, too, we are having too many posts on the forum about amps shutting down or sounding wrong because of poor speaker cable choice.
Tellurium Q, Witch Hat, and Chord are examples of brands producing speaker cables that fit - the forum search function will help.
Many thanks S. Yes, I agree re cost of Kimber and Nordost but I always buy second hand and I find they hold their value extremely well. Anyway, I will certainly take your advice on board and try your recommendations. Is it still longer lengths of these cables being suggested or would 3m lengths be ok? Thanks again
(By the way, I kept editing my previous post while you posted yours, with some possibly helpful clarifications, in case you haven’t seen.)
As for the minimum, see the FAQ. 3.5 meters of NACA5 or 3 meters of SuperLumina are recommended for classic amps like the 250. (Uniti and Supernait are a bit more tolerant but I’d personally not go below 3 m of NACA5).
For 3rd-party cables, it depends on their specs. The length is not the issue, the minimum and maximum inductance and capacitance are. If you find a cable with 3.5 times the inductance and capacitance of NACA5, you need only one meter
Your assistance is really appreciated 
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Just make sure any speaker cable is low in capacitance and moderately high in inductance. FWIW, using Naim’s NACA5 I found that i much preferred the sound performance from longer lengths, 5-10m being much preferred to the 3.5m minimum.
Thanks Richard, what’s the difference between A5 and A4?
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Wow! Thanks for the comprehensive answer K10. I must admit that I’m put off by the stiffness which lots of people allude to causing problems in use. I’ll probably end up buying a few lengths of different types off eBay and doing my own listening tests. Certainly some of the comments regarding potentially frying the amp have really given me food for thought though. Something I’d never even considered in my pre-Naim days.
There are equally many who like the stiffness. It depends on how you have to use it; threading it through holes and bendy trunking won’t be fun. But if you don’t have these constraints, they can be a joy to install IMHO, as long as you remember that you can’t simply toss them to the floor like flexible cables. Instead you have to bend them into the shape that you need. This way, they can be made to hug the wall or skirting, you can suspend them in the air over gaps, and so on, and they keep the shape. IMO much preferable to flexible cables for many uses.
Thanks once again S
When connecting the 272 to 250 DR with the supplied cable, does it matter which of the 2 din sockets on the 272 are used?
No, they are identical