How are cables directional?

Nick Lucid on skin effect:

If you’ve watched those videos (I’m not going to), do they make clear that skin effect has no relevance at audio frequencies in any normal sized cable? Or dk they just explain what skin effect is and leave you thinking it must be important in audio?

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Neither of the videos are about audio.

Well, it may be that there is no measurable effect at audio frequencies, but maybe it’s like the effect that recording and playing back very high audio frequencies (e.g. 30 kilohertz or above) improves the listening experience. There are so many unexplained audio phenomena - it is quite unlike any other electronic or audio application. Like putting spikes on top of the speakers (pointing upwards) can vastly improve the sound.

That’s a new one on me.

Not sure it applies to SL2s.

OK, in order to eliminate any possibility of the effect there are two possible approaches:

  1. Ideally extremely large diameter cables, sufficient so that there is no current at all travelling in the centre, above which there would be no difference however thick - that means a radius of more than 14.6mm for each conductor using copper, so, say, 30mm diameter copper bars for each of the two wire cores to each speaker.
  1. That is likely to be impractical, so the alternative is to use the nearest one can get to infinitessimally thin cores in a multistranded cable, so that regardless of how high the frequency all electrons there will be no skin effect as the cable has no thickness. The thinnest wire commonly available is, I think, 0.005mm2, so a 4mm2 speaker cable would have 800 cores., and would have no known skin effect up to 2.7MHz.

The second option isn’t perfect because there would always be a question about frequencies above 2.7MHz for people with hypersonic hearing ability. so better to bite tge bullet and get those copper bars…

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Stops the cat sitting there?

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There were serious suggestions years ago (1970s?) that you could use 15mm copper pipes with very thin-stranded cable inside (Litz? can’t remember), the idea that the copper pipes carried the bass, and the thing-stranded cable carried the treble.
Never even considered trying it.

Decades ago I wondered about designing speaker cables of probably not dissimilar proportions, for quite a different purpose: At very high frequencies (RF) cables are used that have a characteristic impedance matching that of the load, maximising transmission efficiency. I thought why not gave 8 ohm cables for 8 ohm speakers… I never took it further.

That should be posted as a “FAQ” answer!

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How Are Cables Directional ? :thinking:

In some cases there are little arrows printed on the cable to show the way. :roll_eyes:

In my case the writing of the name and brand goes reading from amp to speaker. :+1:t2:

:partying_face: :crazy_face:

Nobody would be that controversial …

Brilliant

On the basis of this discussion I ordered the book “Lady Tasting Tea” and it arrived yesterday. I have just started reading it but I am quite enjoying it.
Thanks for the recommendation.

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Ah, but are books directional though? :grin:

Not all. Mark Saporta’s Composition no. 1, for example, isn’t.

It’s a box of 150 pages (i.e. not bound), which are meant to be shuffled by the reader before reading in whichever order they end up in.

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I was taught that electrons do not physically flow. They vibrate and pass on energy from one to another adjacent in a certain direction or flow. Oh well.
But wait…no one has (I don’t think) considered the length of the cable. Perhaps only relevant at (much) higher frequencies but can anyone claim to hear a difference because of standing waves due to the cable being cut too short (or long) or pairs are of different lengths?
I’ll get my coat.

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Best.
:wink:

They work best from front to the back.

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Ultimately the answer depends on the technology/ metallurgy within the cable.
If you look at copper under an electron microscope you will witness that it is made up of linear/shard like microfilaments. Whereas silver is made up of circular/spherical like microfilaments.
The way copper is extruded will have some influence in the orientation of its molecular crystalline direction (hence the claims of increasing zeros) whereas silver would be relatively indifferent.
(Only a strictly non professional observation)

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