City dwellers know just how irritating a jackhammer can be. Now there's a way to drone out the racket without closing your window. Scientists have developed a window system that's a gift for your ears, even if it is a bit of an eyesore. Described in Scientific Reports, the Anti-Noise Control Window—to enter production within the next decade—includes a microphone to be placed outside the window to detect the sound waves of incoming noise. A computer then determines the wave frequency needed to neutralize the noise and conveys this to 24 tiny speakers attached to the window frame in a grid pattern. "If you sit in the room, you get that same feeling like when you flick on the switch of noise-canceling earphones," study co-author Bhan Lam of Singapore's Nanyang Technological University tells the New York Times.
But there are limitations. The system isn't great at responding to sudden noises like car horns and firecrackers. It works best on steady noises between 300 hertz and 1,000 hertz, which, unfortunately, excludes human voices. To block lower frequencies, the system would need larger speakers, but that would mean blocking most of the air flow. "In places like Singapore, we want to keep the windows open as much as possible" to limit the use of air conditioning, Lam tells the Times. "Ultimately it is an energy-saving thing," another study co-author, Stephen Elliott of England's Southampton University, tells the Guardian. He describes "a halving of the perceived loudness" in tests. Medical studies indicate such a decrease in noise pollution could correspond with a 7% to 17% decrease in related health risks, per Inside Science. (Read more noise stories.)