Many of us are familiar with that 'phantom' low note effect from telephone tones, some of which are actually produced by playing two higher frequency tones so that we will hear the beat frequency.

I wasn't actually 'fooled' by any of the illusions, but was a bit surprised that the two similar tones, one in each ear, didn't give the beat (at all for me, though my brain was clearly confused about why not), though the bear/fair thing always works. I was a bit surprised by that absence of any mention of reflected sound, particularly regarding positional recognition. It's actually quite importent, particularly to the extent that many blind people make use of a certain amount of echo-location when finding their way around.

Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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