It’s just that, as often, that the scientific worldview and the magical / wishful thinking of esoterics clash here.
So, here are a few facts, accept them or not, it doesn’t matter - they stay facts:
- Every waveform can be represented as the sum of sine waves (Fourier theorem - which is proven)
- To represent a sine wave of frequency f, which is the fundamental to every other waveform, a signal rate of 2f is necessary (which is the Nyquist theorem - which is also proven)
- Human hearing has an upper range of (at most) about 20 kHz, there is no way for humans to detect frequencies beyond this point, we are simply not equipped. Try to receive ultra short wave (FM radio, or “UKW” as we call it in german) with a pure short wave radio - you’ll fail. Epically. Same for your ears… they are an amazing piece of biology, but they simply can’t detect anything
above 20 kHz.
There is only one valid conclusion to all of this:
= A signal rate of 40 kHz + (some space for a super steep, high quality low pass filter) is enough.
And, since the people who build the audio devices KNOW all of that, there is a second conclusion, which I leave up to you to figure out.
A little hint: you can even apply some Mark Twain here.