The "electromagnetic ringing of the ionosphere" is an analogy. The ionosphere does not ring audibly, it's max charge peaks 7 times a second. I've also seen another acoustic analogy of Schumann resonance as a "tuning fork" for the body. Our nervous system are based on clocks much like computers and this determines rhythms like circadian rhythm and even complex stuff like athletic and musical ability. A raise in our biological clock speed could potentially be similar to a raise in the clock speed of a computer, allowing our nervous system to process more information. I'm not positive on your questions about the ionosphere but I believe it's parameters are determined by cosmic rays.
Thanks man, I was a little caught off guard by his comment. Most comments in Qresearch are pointless when Q's not posting, at least I'm trying to do some valuable research.