Thanks, Al. I missed that "10", and if those are 20KHz square waves, that's yet another example of presenting what is tantamount to nearly worthless information and representing it as relevant.
For those who don't understand square waves, their reproduction a particularly difficult test of bandwidth, because to get one to be really square, with nice flats tops and right-angle rises and falls, you need a very high degree of linearity at multiple harmonics around the fundamental frequency. So when Al posits that those are 20KHz square waves, that means that whatever is being tested needs to have great linearity in the 2nd, 3rd, 4th, and so on harmonics. The second harmonic of a 20KHz fundamental is 40KHz. See what I mean? For audio performance a 2KHz square wave test would tell you so much more, but the problem is that the 12 gauge stranded Cu wire would probably look just awesome in such a test too, so they're probably not going to show you the results at 2KHz.
Even with the bogus skin depth calculations, and they appear to be using the right formulae, they aren't telling you that their calculation applies only to solid core conductors. The stranded wire case is more complex, and tends to reduce skin effect even further, which, as I pointed out, is largely irrelevant even for a solid conductor.
So while I agree with Al that Analysis Plus is at least using recognized criteria in their arguments, I just can't give them much credit for it, because they're misusing the information to mislead people, and that's inexcusable, IMHO. How would you like it if your plumber did that? Or your dentist? Or perhaps your accountant?
There are cable vendors around who accurately present information and produce high quality products. These products are worth paying for, and I do it. I use Blue Jeans Cables because I like their quality and service. BJC products aren't the cheapest alternatives available by any means; I like good-looking, high quality products that feel good just as much as anyone else. If people want luxury cables that look and feel like fire hose jewelry, cool. Even pure silver, if that's what rings their bell. What I can't understand is why anyone would want to tolerate a vendor of anything that openly tries to mislead them.
