Sound as we listen is made up of multiple frequencies. The typical way of separating them has been computationally using an algorithm called a Fourier transform. However, researchers in Switzerland have managed to split sound into different frequency by way of a device – a 40cm aluminum case with 10 holes on its sides – almost like a recorder or a flute. The inner area is divided into chambers separated by a membrane that impedes a few frequencies.
The interesting application of this device could be to non-electrically isolate a specific frequency or make an “antenna” like device that would selectively listen to only one band of frequencies. This would be important in problem detection within machinery or other applications like that…
Any other application?