DNM has capacitors with surface treated plates, with slits that smooth out eddy currents.
It came to my mind that since we necessarily have eddy currents in audio cabling, would it be of benefit to have a similar surface treatment for conductors? Lasers would be a quick method of treating conductor surfaces such a way. Maybe eddies aren’t that much of a problem but there’s things like perfect-surface metals that are run through polishing wheels and apparently they make enough of a difference to warrant using the process, so these “small” things are seemingly relevant. Laser treating for uniform surface slits would probably not be that much more expensive than the mentioned polishing process because of the ease of automation.
Then again would this work well for round conductors? Eddies are on the surface so why not? It obviously works in a capacitor since it’s a foil… And foil is used in audio cabling too. It can be a capacitive solution if used singularly so I think foil is better used as a complementary part in a cable. For example, what comes to mind is that for dividing a low impedance pathway for RF to ground, silver foil (or plated) might be beneficial when added to a power cable’s ground. And this could be improved with a slitted surface.
Since transformers especially suffer from frequency dependent winding losses as eddy currents, I could see foil transformers possibly benefiting from such a surface treatment. Might be a bigger benefit than for cables but since this is about cables, let’s consider cables…
Also assumably a properly adjusted uniform slitting does not count as surface roughness which we don’t want.
It seems every cable company pursues the perfect smooth surface. What direction does DMM orient the slits in their capacitors? Sounds like fascinating science.
Van den Hul is an exception for sure, they have cables made of conductive carbon fibers and as of now, also CNT interconnects. From what I’ve gathered from reading about CNT manufacturing for conductors, it is currently not possible to attain a smooth parallel configuration of the nanotubes.
Now, conductive carbons might not be directly comparable to metals in terms of electrical drawbacks so the roughness might not be an issue, I don’t know.
They are interesting cables.
I know of one cable manufacturer that centers their cable design around minimizing the effects of eddy currents. Audience cables sound fantastically good, especially their power cables.
They state they keep conductor mass as low as possible, where the eddy collapse time is much shorter and smears the signal less. I didn’t find statements about other methods of dealing with eddies but yes, the approach is surely effective.
An ultra-thin foil conductor would have the low mass plus it’d be easiest to process the slits onto a foil. Essentially we have the same structure as in those slit-foil caps but unwinded. It works in the caps so it would work in a foil cable, right.
Now the question is, where are foil conductors applicable in audio? They have been used in all types of cabling but it’s questionable where the real merit is. Are they suitable for group delay linearity? Controlling the capacitance? A foil with suitably flexible but robust dielectric could be coiled I guess, to balance out the higher capacitance.
For interconnects I could see not-so-wide foil being pretty good, if it approximately equals a thin 28 to 24 AWG round conductor. But the benefits? Are there even notable eddy currents in what’s essentially a voltage line?
The staggered slit pattern is interesting. I wonder how it affects the magnetic field and eddy current in the foil. It must make the electrons flow easier. It would be neat if they sketched the before and after flow with or without the slits. .
I know first hand using 3M AB7050HF affects eddy current on toroidal transformers and the positive audio benefits of electro magnetic absorption.
I think imaging the flow of eddy currents would require some sophisticated laboratory equipment.
Since they are looping currents on the surface, the slits when properly arranged would break the loops and they might to some degree short out when colliding with themselves in opposition, since breaking them up would surely create enough chaos in their flow to have them change orientation all around and cancelling out. How I see it, but don’t trust me on the latter point.
This would indeed make electron flow easier because by definition the eddy currents act to oppose it. Now, skin effect is actually tied strongly to behavior of eddy currents too. So I definitely see a possible benefit for cables here, with either slits or some other surface treatment applied.