John, I don't know how ears are tracked but the audio is indeed "sent" ultrasonically. The carrier frequency is ultrasonic and is modulated with audio.

Edit: the only way I can see how to ear track is via optics and image recognition. Once located, distance has to be figured out and head-related transfer functions to steer the channel carriers to each ear.

Yup, many drivers. The more drivers, the greater the spatial resolution.

Last edited by Mojo; 11/15/20 07:06 AM.
House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated