Pinholes and Plastic Wrap Make Solid Walls "Transparent" To Sound

First time accepted submitter benonemusic writes "Researchers have devised a means of making sound transmit easily through rigid surfaces, including walls. The process relies on creating small holes on a wall, and covering them on one side with a thin covering made from plastic wrap."

And in other news...

[RdeCourtney]

Researchers find that by putting a glass to a wall, helps sound travel through rigid surfaces as well.

Re:As an apartment dweller

[judoguy]

There is vinyl sheeting for just this purpose.

Mass Loaded Vinyl [acousticalsolutions.com] is a sheet of heavy vinyl that is loosely hung to absorb sound. Usually hung in the wall between the drywall layers for appearance sake, would still work just fine tacked on the outside of the wall separating you from your noisy neighbors.

Of course, sound will travel through the ceiling and floor as well.

Re:Let's see them patent the drum all over again

[sir-gold]

The important part isn't the membrane, it's the fact that the hole was smaller than the wavelength of the sound, which,according to conventional theories about wave propagation, should not have allowed any sound though, membrane or no membrane

Re:Why would you do this

[JustinOpinion]

Well, TFA [insidescience.org] suggests:

The research has potential uses in creating security barriers that permit voice communication to pass through, and in developing types of sound-based microscopes that could find application in research laboratories and medical practice.

The scientific paper [aps.org] further notes:

Such a high concentration of acoustic energy into a small hole of radius enables sensitive detection of acoustic signals with subwavelength resolution ... the present work not only opens the way to the efficient realization of [near-field acoustics] in fluid ultrasonics and underwater acoustics, but also to the analogous realization in solid-state ultrasonics.

More broadly, results obtained for one kind of wave behavior often have implications for other kinds. I.e.: results in controlling acoustic waves sometimes have implications in controlling/sensing light-fields, or radio waves, or even more esoteric things like electron beams or neutron beams (which are also regulated by wave equations).