Interesting soundproofing concept

SonasRec

http://www.newscientist.com/article/mg20527485.400-latex-could-silence-noisy-neighbours.html?DCMP=OTC-rss&nsref=magcontents

Thoughts anyone?

Bosphorus

SonasRec wrote: »

http://www.newscientist.com/article/mg20527485.400-latex-could-silence-noisy-neighbours.html?DCMP=OTC-rss&nsref=magcontents

Thoughts anyone?

sounds very, very expensive

SonasRec

Made from latex and plastic. The raw materials are pretty inexpensive.

Rockshamrover

Sounds like that guy is going to make fortune.

madtheory

They don't give any idea of the amount of attenuation. So I am skeptical. Reminds me of the flat panel speakers that never materialised. These things get reported in "science" journals but they somehow forget the science.

studiorat

Sounds plausable.

iMADEtheBBC

When sound waves hit the panel, the membrane and weighted buttons resonate at difference frequencies. "The inner part of the membrane vibrates in opposite phase to the outer region," says Yang. That means the sound waves cancel each other out and no sound gets through.

Each weighted membrane only cancels out sound waves within a small band of frequencies. But changing the weight of the buttons alters the operational frequency, says Yang. By stacking five membranes together, each tuned to a specific band, you can create a soundproof panel that works in the range from 70 to 550 hertz.

So in theory it works. But doesn't give any indication of attenuation.
If it only works from 70Hz to 550Hz is it really going to make a difference?

PaulBrewer

iMADEtheBBC wrote: »

If it only works from 70Hz to 550Hz is it really going to make a difference?

Anything above those frequencies are a much easier proposition to attenuate.

I've forwarded the link on to Chris in Munro Acoustics for consideration.

SonasRec

Here's some info from a different source......looks like 5 panels stacked and tuned at relevant frequencies provide average 40db of attenuation from 50 to 1000Hz.

As Paul says....above this range is the easy bit.



"The Hong Kong University of Science and Technology has shown experimentally that thin membrane-type acoustic metamaterials can serve as a total reflection nodal surface at certain frequencies. The small decay length of the evanescent waves at these frequencies implies that several membrane panels can be stacked to achieve broad-frequency effectiveness. We report the realization of acoustic metamaterial panels with thickness 15mm (0.7 inches) and weight 3 kg/m^2 (about 6 pounds per square yard) demonstrating 19.5 dB of internal sound transmission loss (STL) at around 200 Hz, and stacked panels with thickness 60 mm and weight 15 kg/m^2 demonstrating an average STL of >40 dB over a broad range from 50 to 1000 Hz.

These noise-cancelling panels consist of a latex rubber membrane stretched over a 3-millimetre-thick rigid plastic grid of 1-centimetre-wide squares. In the middle of each square is a small, weighted, plastic button.

When sound waves hit the panel, the membrane and weighted buttons resonate at difference frequencies. "The inner part of the membrane vibrates in opposite phase to the outer region," says Yang. That means the sound waves cancel each other out and no sound gets through.

Each weighted membrane only cancels out sound waves within a small band of frequencies. But changing the weight of the buttons alters the operational frequency, says Yang. By stacking five membranes together, each tuned to a specific band, you can create a soundproof panel that works in the range from 70 to 550 hertz."

madtheory

AFAIK you can get better attenuation in a similarly wide space using well established building techniques, such as those described in the MAster Handbook of Acoustics.

But it would be very cool to hear what Chris has to say Paul!

PaulBrewer

madtheory wrote: »

AFAIK you can get better attenuation in a similarly wide space using well established building techniques, such as those described in the MAster Handbook of Acoustics.

But it would be very cool to hear what Chris has to say Paul!

So for a given depth of 'regular' soundproofing one might expect the same performance ?

madtheory

I'm not sure Paul. Chris will know

culture vandals

studiorat wrote: »

Sounds plausable.

we'll have to get the myth busters on it lol