Vibrating windows cancel out noise

Researchers in Germany claim have applied the same technology used in noise-cancelling headphones to windows in a bid to make houses quieter.

The system developed at the Fraunhofer Institute, where the mp3 was invented, gets rid of low audio frequencies like those emitted by aircraft, road traffic and booming discos. Higher frequencies are naturally filtered out by glass panes.

Thilo Bein, who manages the institute's energy, environment and health department, claimed: "The perceived noise indoors is only half as loud.”

The technology captures the offending sound and creates further sound of the same frequency but with the opposite phase. This anti-sound is then emitted into the room using a thin chip of piezoelectric material. The result is the window pane physically vibrates in the opposite direction to the sound waves.

The new active noise-reducing windows could be on the market in about four years, according to Bein.