‘Audible enclaves’ could enable private listening without headphones

Submission Statement:

UNIVERSITY PARK, Pa. — It may someday be possible to listen to a favorite podcast or song without disturbing the people around you, even without wearing headphones. In a new advancement in audio engineering, a team of researchers led by Yun Jing, professor of acoustics in the Penn State College of Engineering, has precisely narrowed where sound is perceived by creating localized pockets of sound zones, called audible enclaves. In an enclave, a listener can hear sound, while others standing nearby cannot, even if the people are in an enclosed space, like a vehicle, or standing directly in front of the audio source.

In a study published today (March 17) in the Proceedings of the National Academy of Sciences, the researchers explained how emitting two nonlinear ultrasonic beams create audible enclaves, where sound can only be perceived at the precise intersection point of two ultrasonic beams.

“We use two ultrasound transducers paired with an acoustic metasurface, which emit self-bending beams that intersect at a certain point,” said corresponding author Jing. “The person standing at that point can hear sound, while anyone standing nearby would not. This creates a privacy barrier between people for private listening.”

By positioning the metasurfaces — acoustic lenses that incorporate millimeter or submillimeter-scale microstructures that bend the direction of sound — in front of the two transducers, the ultrasonic waves travel at two slightly different frequencies along a crescent-shaped trajectory until they intersect, researchers explained. The metasurfaces were 3D printed by co-author Xiaoxing Xia, staff scientist at the Lawrence Livermore Laboratory.

I would rather they figure out how to completely block external sounds than figure this out. We have headphones for decades and people still use speakers in public.

And no: noise cancelling headphones or earplugs are not sufficient. Besides, it’s someone else making noise, they should be the ones adjusting, not anyone around them…

And given how people behave, even if this technology was cheap and accessible, people would still not use it and bother others.

It exists already for a while. By using wave interference to promote harmonics of ultra sounds waves you can already generate sound in a specific direction. The main issue is the low quality of the sound produced, noticeably the almost non existent bass.

as someone with misphonia, I hope this becomes reality soon cause this could change lives for some of us.