Oster's Curve gives insight to why the threshold is 1500 hz.
The auditory illusion is not perceived anymore.
This research is from Monroe if I'm not mistaken.
I'll try to follow up with credible citations when I have the time.
Cannot deny the possibility of weak magnetic fields or other phenomenon.
It's all energy, you can use different systems of measurements to see different things; as long as it is in range of the spectrum for the device measuring it.
Regardless, it starts from a mechanical nature; your brain perceives it as electrical in the end. So you can describe it in various mediums.
You have excellent insight.
I will try to follow-up with source citations when my schedule frees up more.
Thank you for the thread.