Speaker Cable + speaker impedance

Please forgive me for bring this up again. I have searched both current and archived topics. Does the speaker influence the minimal cable length recommended by Naim?

Sorry if this question is redundant and or dumb


No - the minimum length is to make sure the amp has the right impedance on its output stage. Nothing to do with what’s on the other end of the cable (AFAIK).


Seems like the speaker impedance would influence the minimum cable length requirement, thus impact the cable length. Previous topic discussion were relevant to the cable impedance only.

No, Naim power amps do not have extra inductance on their outputs (gives best sound), instead, in order to maintain stability, they rather elegantly use the speaker cable. They require a cable that provides a nominal inductance along with a low capacitance, something that NACA5 ideally provides, subject to a minimum 3.5m length per channel. The speaker itself should not influence this.

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So a 4 ohm speaker or a 8 ohm speaker makes no difference?
Thank you

If you mean does it make any difference to the speaker cable requirement of Naim power amps, the answer is no.

Ok. I was hoping for a different. Answer. I want to use 3m of Chord music cables. The specs of the Chord don’t seem to be available. Am I going to impact SQ or cause problems for my 500 with the shorter length.

The 3.5m minimum recommendation only applies to NACA5, due to its electrical characteristics. To find out the minimum length required for any other cable, you’d need to know that cable’s electrical characteristic and do the necessary maths.


Unless they highly capacitive or of very low inductance, I doubt they will cause the NAP500 distress. As to how performance will be impacted compared to longer lengths I couldn’t say. Comparing NACA5 lengths, I definitely preferred 5m over 3.5m per channel, and liked 10m the best (the difference between 5m and 10m was much smaller than between 3.5m and 5m.). For want of a better word to describe it, I found that the longer lengths allowed the music to “breathe” better.

I’ve used Sarum (3.47m) and Sarum T (4m) with a 500 for a few years with excellent results, and certainly no damage to the amp. There’s at least one member here running Music with a 500 with stonking results (though I’m not sure what length he uses).


Thanks everyone. I can’t seem to get the cable specs from Chord. Tried emailing twice.

If they or you know the physical dimensions then the calculator here can work out the inductance:


You require 1uH per metre to match A5. Note: it is diameter of wire required so if figure given is square area you will need to convert!

Note2: some upmarket cables allegedly have some magnetic material in their insulation. In this case the permittivity would presumably no longer be 1.

Richard surely the speaker can influence this, as the amp will see a reactive load consisting of the voice coils, loudspeaker enclosure, crossover(s) and speaker cable.
I believe the Naim guidance on NACA5 covers the vast majority of designed speakers, but some highly capacitively reactive loads with some sorts of exotic tweeter may need extra consideration, or other speaker designs may comfortably work outside the stated NACA5 guidelines… but best play it safe…

Thanks Simon. My point was that in the context of Naim’s recommendation, it should not change that.

Indeed, thanks

The excellent Naim dealer I bought my Nait 5i from was insistent i used 4+4m of Naim cable, i got it free with banana plugs fitted. It was used in a small room and the cable was forever getting in the way. 15 years later its 1+1m of skinny QED connected to Unitiqute 2, much more compact and bijou!

Hi Dan,

You really have no reason to worry. Music speaker cables and 500 are a sensational combination. They will not adversely affect sound quality based upon any difference in specification of NACA5. Quite the opposite in fact - I’ve used both.

IF, and I use that very speculatively, you were using a CB 250, you might possibly have an issue, but I doubt it. Remember, Chord was initially established to build cables for Naim - RCA to Din IIRC.

Buy with confidence, after trialling them of course.

Exactly right, however the 3μ5H will protect the amp against significantly capacitative loads, for many speakers (principally moving coil tweeters) the load presented has a more inductive characteristics at high frequency, in which case less than 3μ5H in the speaker cables will still be adequate to protect the amp even if this doesn’t make for the best sound quality. On the other hand how many speaker manufacturers actually publish the inductance of their speakers at 50kHz for you to work this out?

As you say 3.5m of NACA5 (i.e. 3μ5H) is still Naim’s recommendation and should be respected.
Further than this, you yourself have pointed out the sonic benefits of using more than this to give additional help to the performance of the amplifier.

Someone in all these years must have hooked up a Naim amp and speakers with piezo tweeters. Maplin used to do a kit and there’s always one, source first and all that. Would 3.5m of cable be enough?