Longish post got 502'd
"what kinds of sounds can I pick up, which we don't normally notice?"Any interest in trying to make the infra sound real-time hear-able?
I tried just adding/mixing some 400-600 Hz at amplitudes above and below that of the infra sound, that did make some of the VLF changes hear-able.
I tried fully modulating the amplitude of 400-600 Hz with the VLF, that was better at making the VLF changes hear-able. I can't figure how to simply do FM.
These first 2 were very tiring to listen to for the VLF changes, even for just a minute or two.
I tried just squaring up the VLF comparator-like, that seems to be the best so far in making the VLF changes audible.
The squared up version sounds very much like a buzzing bad connection, I think this version is worth a few more lines of C, - a 50 sample running average to accurately follow the the mid-level, and at least some variation to the square's height/volume based on the actual current p-p height of the VLF. The running average is easy enough, I'm still thinking on the
reached peak detection. I'll post an audio sample
when if I get anywhere.