Speaker cable

Good morning does anyone who have bought 350’s know if you can run them with shorter cable than the normal 3.5 meter

The manual says suggest avoid sub 2Ms.

Am using 3 m run

You can run them with any length you like unless it is a very old Naim amp. It’s not a problem. But if you happen to be using a Naim speaker cable, it sounds better if longer than 3.5m. If you are using something else, you’d have to experiment to see whether it sounds better shorter or longer.

Earlier Naim amps usually sound better on say 5-8M length.
Valid from 80’s amps to a 250DR at least
No experience with NC range but doubt that has changed radically - why compromise ?

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Assuming you are talking NACA5. Naim’s new designs are not so critical now in terms of avoiding destructive oscillation, but they recommend avoid less than 2 metres per channel for optimum SQ.

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As Simon say you need little inductive load towards the high frequrncy. That could be build in the amp, old series does not have it, and thus use more inductive cables. However it also depends on your speakers, more precicely your tweeter network. If you measure your speakers impedance along the frequency responce and you find out they are slightly inductive you do not need additional inductance from the speaker cable and can go for zero inductance cables or short cables. I use dyton audio impedance measuring device, comes pretty usefull for other things too, like measuring your cables, drive units, etc.

My system at present 552 dr 300 dr 333 streamer xps dr BW 804d4 was thinking about chord signature xl or Sarum also will probably go for 350’s

[quote=“tgw56, post:9, topic:34111”]
1221BW804fig1
hi TGW56, looking at your speakers impedance , more specifically the phase shift in high frequency range in your case is bellow zero and that indicates you have capacitive load and with NAP300 you need inductive cables, how long I cannot say without measurements of cables and speakers together, but would say don’t go below 5 meters. these speakers are quite difficult to drive at 70 Hz, the phase is -70degrees. Disclosure: I am not an audio engineer (i have MSC Nuclear Power Engineering) and audio is a hobby for me, so would be good if someone else could confirm that!!! The graph is taken from Sterephile, using same Dayton Audio’s DATS v2 that I use home.

Contrast that with Naim’s own NBL, yet they still sound better with 5m of A5 than 3.5m.

image

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I loud speaker system is typically a complex load in terms of impedance so will contain capacitive and inductive elements at different points in the frequency band pass.
My observation of that chart, is that looks quite a challenging loudspeaker to drive for an amplifier. But regular largish gauge speaker cable like NACA5 would be fine, though I would avoid very long lengths, or extremely short lengths for most amps. For older Naim amp designs, 4 to 5 m is often a sweet spot.

Do remember with loudspeakers if a critically measuring the impedance, you need to it with a signal generator when it’s generating audio in the room, as the room coupling will affect the reactive elements of the impedance. Looking at a speaker impedance graph passively decoupled from the room it is in could be a little inaccurate. Not sure Stereophile magazine did this ! Possibly accounts for it sounds better than it measures statements you see from time to time, as well as some speakers needing a bit of loudness to ‘wake’ them up.

What a superb speaker the NBL was! Those bounds of being well within ±22.5 degrees is remarkably narrow - in fact I don’t think I’ve ever seen it before. (I can do 37.5 deg all day with a closed box but this is significantly narrower and shows they didn’t skimp on box size.) It’s a shame so few people “got” them.

The cable won’t really affect what’s going on down at 70Hz and certainly not in terms of inductance. I’d be a little more concerned at the top end where it’s about to go through 0 degrees just above 20kHz. It might be nice to have this already inductive but so much of this is a matter of chance, not least because you can get ringing on the output that has nothing to do with the amplifier becoming unstable (and this is something you can unpick and show that the frequency of ringing is exactly what you’d expect from the values of the inductance and capacitance). I’d like to see a more comprehensive set of measurements from JA (I assume this is JA) before thinking to act on them, perhaps including square wave performance. I think I’d just trust Naim when they say their amplifiers are stable. We haven’t seen a Naim amp blow up of its own accord for at least 4 decades - certainly I haven’t - and back then people could have been using almost anything to connect the speakers. And NACA5 is such an extraordinarily good cable that I would want to use anyway. (I have been told on good authority that Chord can do a tiny bit better but with quite a serious price hike.) I don’t think it’s a huge leap of faith to just go with the Naim recommendations and, when it comes to choosing length, I would bear in mind the lengths of cable they themselves would be using when listening/auditioning their own products. I’m going to guess that starts at 5m, but it might be 8m in a large listening room. I think I’m right in saying that the general feeling was no one could tell the difference between lengths above 5m, though I’ve never owned NACA5 longer than 5m so can’t confirm this personally. But it makes sense as the cable has a very low resistance of about 0.02 ohms round-trip, IIRC, so you’re just adding a fraction of that as you go up in length.

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“The cable won’t really affect what’s going on down at 70Hz and certainly not in terms of inductance.” Indeed, but what makes you think I have said that? Can you quote me?

Please excuse my lack of knowledge of these curves. Could someone please tell me which curve is which. I assume one is for impedance and another for phase.

Warm regards,

Mitch in Oz.

Solid line is impedance, dotted line is phase.

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The DCR of 5m of this cable is about 0R02. The voice coil will change resistance, probably within a cycle, by that amount at some not unreasonable listening level. Besides, the variance of the voice coils will probably be 10x that amount.

Dear @Christian_Thomas , I feel you may not have read the full post from start to end. Power amps need little inductive load the high frequency to avoid oscillations. Of course drive units have enough and if you run active you are OK, but if you have passive XO there are usually capacitors in the network and the overall high frequency load may become capacitive instead of inductive, like in the particular case we are talking in this post. To avoid having discussions like this most audio system manufactures put little coil at the output stage. However the inductive element deteriorates the overall sound quality and on top of that most speaker cables have inductance anyway, so thus Mr. Julian Vereker has decided not to use inductive load at the output stage, but use the inductance of the cable (part of PRaT philosophy) and this Naim speaker cables have one of the biggest inductance per meter if you make the effort to compare some.

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In front of “these” there is a full stop. It separates two sentences.