An “acoustic metamaterial” that can cancel 94 percent of sound

Re:An “acoustic metamaterial” that can cancel 94 percent of ... by edejong on Saturday March 09, 2019 @03:59AM (#19345206)

The article mentions using feno-like resonance to transform the frequency response (and phase). The effects of this are localized to a frequency-band around 440 Hz. Interestingly, this is a similar effect as mie-scattering.

Therefore, I am not sure the common knowledge of bass-traps and heavy materials for muffling sounds are actually applicable here.

I suggest reading the article and studying feno resonance.

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Re:An “acoustic metamaterial” that can cancel 94 percent of ... by tmikaeld on Saturday March 09, 2019 @05:57AM (#19345597)

And if I'm not mistaken, Fano resonances only work in a controlled environment like headphones (noise cancelling).

My comment wasn't a comment to the test in the article, but the expectations of the article - that any sound can be blocked, the writer is implying that this can be built into anything "a quieter world", which is not true for low frequencies which can't cancel itself out (without a very controlled environment like two subs of the same size in a cabinet, or an MRI machine) simply because it passes through objects and don't bounce.

I've seen noise cancellation concepts for the real world before, where a unit is placed on a window to cancel out outside noise by matching the vibrations of the sound.

In practice however, the sound waves are not predictable without a controlled environment, so it's just vaporware/concept [1].

[1] https://www.youtube.com/watch?v=Mv6sBuwzLhk

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Re:An “acoustic metamaterial” that can cancel 94 percent of ... by Gatsky on Saturday March 09, 2019 @04:23AM (#19345294)

It's Fano resonance.

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