Acoustic Cloaks

Very special approach in designing the acoustic cloaks chose Steven Cummer, scientist at Duke University, professor of computer and electrical engineering.
Knowing great power of sound waves he chose gradual suppression of sound waves by creating multi-layer plastic sheets with sophisticated holes pattern: the acoustic cloak of next generation.
The device has a shape of a pyramid, and is made with a 3D printer.
Nothing supernatural, yet the effect is profound - the sound device placed under the acoustic cloak pyramid appears as it is not there.
No known nanomaterial was used which raises the potential for commercial applications. Concert halls and stadiums could benefit from this technology soon.