Naim 'Hiss' active Vs passive pre

[Richard.Dane]

Most odd. I guess it could be a few things; it may be down to an odd acoustic effect in your room. It could be some kind of RF interference. It may be down to ethernet over mains devices (if you have these get rid ASAP - horrible things that can cause no end of issues with high end hifi).

[feeling_zen]

Although my earlier hypothesis was rejected, it may still be worth using an RF meter to measure and compare RF interference at home versus the dealer’s dem room.

[Suedkiez]

And even though the hiss seems to have other causes, there’s now yet another cable in the mix that’s at least questionable:

Speaker cable: Ricable

Do you know the full specs? I can see it’s around 3 times more capacitive than NACA5 but can’t see the inductance figure. Which amplifier are you using it with?

I just don’t get it but tired of repeating myself

[Donato]

Hi,
not ignored, but i do not have the meter. need to get one first.

[Donato]

please find attached screen shot with specs of RICABLE speaker cable.

[Suedkiez]

Can’t find it, where is it attached? I did look for the specs previously but could not find any, including on their website

[Donato]

[Suedkiez]

Thanks, I did miss the capacitance value and the description when I looked earlier. The capacitance at 70 pF/meter is not extremely high, but it is 4.3 times higher than NACA5, which has 16 pF/meter. That might turn out OK, but unfortunately they are not telling us the inductance in these specs.

I can’t look inside the cable on the photos, but based on how they look (round and fat), and the description, I would expect low inductance. This would be typical for the construction that they describe in the specs: 224 wires in 7 braids of 32 conductors. It’s exactly what I cautioned against in the earlier post:

Naim 'Hiss' active Vs passive pre

Ok. It’s not ideal and I don’t know why there is a continuous stream of forum posts because dealers use speaker cables for Naim amps with unknown or unsuitable properties. Anyway, do you have a name for these cables or a photo of its cross-section when unterminated? Usually it’s possible to get an idea based on the construction: Anything similar to NACA5 is typically OK: Two strands of cable (one stand each for plus and minus), the wires within one strand not internally isolated, with a dista…

I.e., “Anything that is braided or litz type (wires within a strand being individually isolated and woven together in a pattern) are usually unsuitable for Naim amps”

And this combination of low inductance and high-ish capacitance would not be good, because you would need many meters to reach the recommended lower limit of inductance (NACA5 has inductance of 1 μH per meter, and recommended minimum length is 3.5 meters per channel, ideally 5-10 - as mentioned in the FAQ) and this would make capacitance quite high at the same time. (And is expensive and inconvenient by requiring many meters). We can’t be sure, unfortunately, without having the inductance value.