Bah. I thought this was going to be cool passive noise reduction but it’s active.
Back in the 90’s someone figured out these little hollow beads that ate sound. They talked about how we could paint them on walls to dampen whole rooms, or things like airplanes.
Since we never heard from them again, even after the patents would have expired, I suspect that they couldn’t find a binder that adhered to the beads without filling in the holes. Or the paint neutralizes the effect.
Two modes are described, one is direct acoustic interference. That one's an active mode where sound waves are cancelled out and the fabric effectively is "just" a speaker. The second is a passive method where the sound is dampened by way of sinking the current produced by the piezo fiber.
Back in the 90’s someone figured out these little hollow beads that ate sound. They talked about how we could paint them on walls to dampen whole rooms, or things like airplanes.
Since we never heard from them again, even after the patents would have expired, I suspect that they couldn’t find a binder that adhered to the beads without filling in the holes. Or the paint neutralizes the effect.