buzz, he did not mean impedance. He meant AC resistance! When I was writing earlier I found a clear description of AC resistance but google is resisting (or impeding) my search for that description. It's at
[Link: en.wikipedia.org].
So buzz misunderstood what was meant by AC resistance, as I did. That's because it looked like a mistaken term, it's arcane, is unrelated to audio, and was introduced without giving the definition at first. The following is from a wikipedia article on skin effect. I've highlighted the parts that relate to this discussion.
Skin effect is the tendency of an alternating electric current (AC) to become distributed within a conductor such that the current density is largest near the surface of the conductor, and decreases with greater depths in the conductor. The electric current flows mainly at the "skin" of the conductor, between the outer surface and a level called the skin depth. The skin effect causes the effective resistance of the conductor to increase at higher frequencies where the skin depth is smaller, thus reducing the effective cross-section of the conductor. The skin effect is due to opposing eddy currents induced by the changing magnetic field resulting from the alternating current. At 60 Hz in copper, the skin depth is about 8.5 mm. At high frequencies the skin depth becomes much smaller. Increased AC resistance due to the skin effect can be mitigated by using specially woven litz wire. Because the interior of a large conductor carries so little of the current, tubular conductors such as pipe can be used to save weight and cost.
And
‹The ratio AC resistance to DC resistance of a round wire versus the ratio of the wire’s radius to the skin depth.
The second quote is from the legend of a graph.
NONE OF THIS DISCUSSION MENTIONS INDUCTANCE AT ALL. g007 decided to make reference to a term that I've never seen in any discussion of resistance or impedance, ever. That doesn't mean it doesn't exist. That means it's outside the sphere of what we're dealing with and talking about.
I think the most important fact to notice from this is that the "skin" at 60 Hz is 8.5 mm, which is about a third of an inch. That is, any conductors less than a third of an inch in diameter WILL NOT SHOW ANY SKIN EFFECT. (Zero gauge wire is just slightly smaller than a third of an inch.)
This is why I say the entire issue of skin effect and the g007's use of the term AC Resistance has no place here. It makes absolutely no difference to anything we're talking about.
