Total posts : 45366
Your questions are out of the ballpark for me, except that I can talk about it anyway.
The math is on my list of “must learn” stuff. But I will guess that the lowered impedance of 4 wires in parallel might be close to that of a very large solo copper pipe.
I haven’t yet built the coil to go with my AM cage, but when I do I will use that home remedy of trying different taps until I find a peak in power.
Just tuning it up with a stock SStran3000 (unmodified) at 1680kHz lowers my S5 setting from 82uH, the normal setting for a single wire, down one notch to 138uH.