hinkley 3 days ago

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.

3
axoltl 2 days ago

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.

djusk 2 days ago

Unfortunately the passive method is not very effective at blocking sound, 75% is only about 5 dB.

sgt101 3 days ago

Why wouldn't you just quilt them up in lots of pockets and then attach them like wall paper?

shakna 2 days ago

Those sound similar to maybe SiLibeads? Which are widely deployed into factories but doesn't real turn up in more daily spaces.