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

As far as deep bass goes, this won&#x27;t hinder that - since bass waves have too high of a pressure to not pass through the object.<p>The most effective material is high mass and flexible, like cork or hemp crete.<p>Bass-traps also exist, they eat up the energy of sound pressure and are usually large tubes and many of them are needed to make a difference.<p>So there&#x27;s a reason that this test is on high-frequencies, not low ones.<p>EDIT: Fine, down-vote me if you want but it doesn&#x27;t make it less true [1]<p>[1] <a href="https:&#x2F;&#x2F;www.acousticfields.com&#x2F;how-do-you-stop-low-frequency-issues-in-a-small-room&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.acousticfields.com&#x2F;how-do-you-stop-low-frequency...</a>

&quot;Cancel 94%&quot; sounds like a lot, but that&#x27;s just -12dB — significant, certainly, but nowhere near making audible sounds inaudible.

I feel like a lot of the comments here are missing the point because this isn&#x27;t a magic noise-cancelling material.<p>The neat thing about this is that it works while still allowing air to flow through. Even if it&#x27;s not blocking broad spectrum sound, it&#x27;s still useful to block specific narrow frequency ranges. One immediate application mentioned in the article is for drones, which are very loud. Maybe if you put these devices below the fans of a drone, you could make it run much quieter.<p>It also establishes acoustic metamaterials as a new field of study, so we could soon see significant improvements in this technology - imagine a dynamic version of these rings which can change the frequencies which they block.

Did... no one read the article before upvoting? This can reduce specific frequency sounds by -12db, NOT 94% of &quot;sound&quot;. Can &#x2F;u&#x2F;dang or someone edit this clickbait title?<p>The wavelength of 100hz is 56.5 <i>feet</i>. While it may be possible that these rings can attenuate <i>specific high frequencies</i>, they don&#x27;t [and cannot] reduce all <i>sound</i> in general. To say otherwise would be to defy physics. Assuming the rings aren&#x27;t vaporware, they could work for specific, constant higher frequency sound sources, like machine hums as mentioned in the article. However, the rings&#x27; aesthetic would be useless inside of an MRI machine...<p>There is a reason existing sound barriers aren&#x27;t open, because even regular walls block high frequencies. (And not just specific ones that match to a ring&#x27;s size). The best way to kill frequencies are thick objects (like walls). For a room (like a editing studio or recording booth), it should have a non-symmetrical wall with various recessed spaces to function as sound baffles, at the least.<p>And lastly, these would be completely useless for low frequencies.

The title of the article is incomplete. It should read<p>&gt; An “acoustic metamaterial” that can cancel 94 percent of sound _at one frequency_.<p>I don&#x27;t see how that could counter the turbulence generated by a jet engine. Maybe that was just the journalist getting ahead of themselves.

The article implies that the test stand was running at a fixed frequency. This makes me suspect that this has to be designed to interfere with transmission of sound at a specific frequency, and perhaps isn&#x27;t capable of eliminating more complex sounds like voices or music.

As someone with disposable income working in an open office, I desperately want to know if this can be used to build something to cancel out human voices more completely than Bose QC-35s.

Like others here, I wonder how well this really works, but I applaud the effort nonetheless and I hope to see progress in this area in the coming years!<p>Better sound blocking tech would really improve people&#x27;s lives and stress levels, especially people who can only afford to live on busy streets in old apartments without proper sound proofing. No to mention people who want to do music in their apartments without bothering their neighbors.

If affordable, all I can think about is how much this could help musicians or bands that practice at home without disturbing the neighborhood.

Too bad sound perception is logarithmic. 94% is nowhere near as much as one would be led to believe if one did not know what a &quot;decibel&quot; is. Which is just as well I suppose: makes for a very nice, clickbaity headline.<p>_Many_ people don&#x27;t get this. People are surprised to discover that a 10W guitar amp is not that much quieter than a 100W one, and even 1W amp can be pretty darn loud, even though it&#x27;s just 1% of the power.

What does it mean to “cancel” or “block” “94% of sound”? From the paper’s abstract: “Finally, the proposed unit-cell performance is validated experimentally, demonstrating a reduction in the transmitted acoustic energy of up to 94%.”<p>Does this basically mean amplification by about −12 dB?

Just couple of points about the article. 1- the main focus of the study is to silence the sound while maintaining ventillation, i think comparison with the barrier is not relevant. 2- the structure is deep subwavelength compare to the mufflers size 3- low frequency can still be silenced with this design but need an stiffer material maybe metal 4- experiment is design considering both fabrication limitation ( 3D print size) and the tube material to be effectively work as a waveguide

In physics we are learning about sound waves, and how noise cancelling headphones detect noise and produce waves which are destructive to those incoming sound waves, by matching the amplitude and sending them out at a different time interval. I think future noise cancelling materials will make use of some kind of tech like this.<p>I don&#x27;t think materials that simply absorb sound are very efficient.

<a href="https:&#x2F;&#x2F;journals.aps.org&#x2F;prb&#x2F;pdf&#x2F;10.1103&#x2F;PhysRevB.99.024302" rel="nofollow">https:&#x2F;&#x2F;journals.aps.org&#x2F;prb&#x2F;pdf&#x2F;10.1103&#x2F;PhysRevB.99.024302</a><p>Anyone have access to this paper? This is driving me nuts and I want to know, damn it :P

So what are the best, most creative ways to get rid of freeway&#x2F;steeet noise from your yard?

Is it possible to build this at home using a 3d printer ?

It places the lotion in the basket...

As a side note, I know that I am old (and grumpy) but was it really necessary for the actual engineers to pose for the leading article picture?<p>I mean if it was a journalist&#x27;s or editor&#x27;s choice to <i>mis-</i>illustrate the invention creating a picture with models I would be fine with it, but the actual engineers&#x2F;inventors posing for it?