I've read an article about this in some German weekly paper when I was like 18?
Was hoping for this to come to fruition in a couple of year's time. But patience always wins, right?
I also remember reading about stationary ANC embedded in buildings at that time.
Unfortunately, the only magazine article from that time that I remember and that has become reality, is the one about identifying individuals in "anonymized" location traces, using very few data points.
This is clever engineering, but it's not sound that "bends itself" through space. The sound isn't changing direction in air - it's following paths created by the acoustic metasurfaces, and the audible sound is only generated at the intersection point of the two ultrasound beams.
Speakers that operate like this have been around for 30+ years under the name hypersonic sound. The original company “HSS” went under and/or pivoted to making Lrads.
You can still occasionally find their speakers on ebay.
I bought one 16 years ago. It was pretty fun but definitely did not have the promised fidelity… the range and directivity was everything and more than it promised. We tested it out to a mile and could still hear it. Very cool.
I’m firmly convinced that a lot of the acoustic tricks that AirPods Pro do to achieve noise canceling involve ultrasonic harmonics, perhaps unintentionally - and this has created an epidemic of tinnitus among their users.
Interference patterns. Cool stuff. Made me think of the 3brown1blue video on holograms... that one blew my mind but that's par for the course for 3b1b...
