So if we talk about cables from other brands whose electrical values are not known, what should we do? I have 2m of Tellurium Ultra Black II, similar cable topology of NACA5 but parameters are unknown.
Simple. Ask the makers what the Electrical characterises are for their cable.
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I’ve found something on Tellurium Q Black II, some comparison with NACA5:
Tellurium Q’s Ultra Black II is not – as I had thought – the range topper in the catalogue (there are several tiers above it and even more below). But, it’s a large range of cables to choose from and I guess that you have to use your budget to determine what level to start at. TQ Ultra Black II speaker cable has a wide (40mm) and fairly flat construction with conductors spaced apart in the style of Naim NACA5 but considerably wider. An inner plastic covering of some kind (PVC?) has a woven cover that terminates in nicely finished aluminium fittings where flying leads are used to provide flexibility of connection. Termination can be a spade or hollow banana plug; our sample was supplied with the latter. No indication is given as to the nature of the conductors, but the wide spacing means that the cable will have high inductance and low capacitance.
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Cable inductance is normally set by the spacing between +&- conductors.
Wide spacing gives a higher L ( lower C) , parallel pairs & twisted pairs will have less L , the various interwoven & Lltz types are low L (& high C)
The Tellurium cables with the various spaced conductor designs will all be high L & low C,
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Using cables other than Naim is easy. The specs per metre are not what should be compared. It’s the specs over a given length of cable X and whether they fall into Naim’s comfortable min and max values.
I had previously posted a table based on taking the specs of A5 and Superlumina at 3.5m and selecting whichever had the lowest and then again at 17m and selecting whichever had the highest. This gives you your acceptable window. You might have a cable that has very high capacitence but only want 2m runs which equals 10m of A5.
The table post was removed I think but people can do the math themselves.
Luckily n-lot did the same here 
I hope it won’t be removed (I don’t know why it would)
… you mean inductance - not capacitance (??)
Bear in mind that the cables need to have a combination of low capacitance and moderately high inductance. The combination is the key.
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No I’m referring to the scenario where Naim amps don’t play nice with high capacitance cables. So a cable might be much higher capacitance than Naim like compared to A5 but given the length, perfectly fine.
Inductance would be the other way. They want highish inductance and maybe the cable is on the low side but you want 12m which is about the same as A5 at 3.5.
Sorry feeling-zen, but that doesn’t work
The most important factor for Naim amps is inductance, this is needed to stabilise the amps output stage, ideally a minimum of 3.5uH
Capacitance is a secondary consideration - useless it is so excessive as to raise capacitive reactance to the point of causing output stage oscillation.
Cable construction & its conductor spacing, (assuming its just a cable & no added networks) will give either high L with low C, something in the middle , or low L with high C.
Therefore if you have a very high C cable & just use a short length to minimise possible output stage stability problems, then L will be extremely low & will not give anything close to required L load.
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Hi Mike. Reading your post above I read it that Tellurium cables have the required low capacitance and high inductance, due to the construction. Is that correct please? My 4.5m pair of Black II seem to be fine. They are interesting cables, with two tiny wires for positive and two for negative, each in a yellow cable, and then inside the black covering. The picture shows a split cable with the little wires exposed in either positive or negative. They are certainly very different to the much heavier A5.
I have Audience AU24 SX , recommended by my dealer. He recommended me also Kharma.
I tried to search the specs for these cables, but couldn’t.
Another member asked in another topic if Shunyata cables could match.
Same problem, impossible to find the specs ( capacitance and inductance).
I feel most brands don’t publish them unfortunately.
Surely cables have to be looked at in conjunction with the relevant crossover network and can’t be considered standalone?
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I just use NacA5. Naim recommend it and it sounds fine to me. One less thing to worry about.
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Hi Nigel, howzit all going at Emsworth Manor ??
As I understand it with Tellurium, they are all high L & low C, but as we all know they refuse to publish any specifications so who knows for sure. All a bit silly really its easily measured with a simple multi-meter.
I read on a www post a while back that the old TQ Black measured 1.2uH/m & 1pF/m. I can believe the inductance as is close to what I calculated using cable design software, not so sure about the very low C, but if it is close to being correct then its even more perfect for Naim amps.
All good here thanks. What confused my was L for inductance. You’d think it would be I.
L is used after the electromagnetics (induction) pioneer Henrich Lenz.
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Fitted the new to me naca5 cable to my system and wow what have I been missing !! System just sounds more together and everything just sounds more clear , vocals instruments and the clarity has definitely stepped up a few notches . Just sounds more pleasing to the ear . Very impressed indeed .
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I wonder what the copper area is of those Tellurium. I have them and believe they sound great but I would have hoped it was more copper in them. Not sure if I should care as long as it sound great but…
And “I” is for Amps-current 