Researchers have developed noise cancelling technology that allows open windows to block noise
Spotted: Anyone who lives in a big city knows the routine – you open the window to get some air and are instantly assaulted by the noises of urban life – the cars and trains, arguments and loud dogs. Researchers in Singapore may now have a way to help block this out. They have developed an apparatus that works like a pair of noise-cancelling headphones for your windows.
A team of researchers at Nanyang Technological University in Singapore developed a prototype, called the Anti-Noise Control Window, that expands the concept of noise-cancelling headphones to encompass an entire room. The prototypes consist of 24 small speakers that are placed in a window and emit sound waves that correspond to incoming noise and cancel it out.
To capture incoming sounds, the system uses a microphone positioned outside the window to detect sound waves, and a computer controller to determine the wave frequency needed to neutralise the sound. This is then transmitted to the speakers on the window frame.
Researcher Dr Bhan Lam, at Nanyang’s Centre for Information Sciences and Systems, explains his interest in the project: “I grew up in Singapore. It’s a small city with a lot of noise, so I have some motivation to solve this problem.” The system is best at moderating the types of steady noise sources found between 300 and 1,000 hertz. Unfortunately, this does not include most human voices. Thus, one of the next hurdles will be to find a way to muffle loud conversations.
Noise is one of the banes of modern existence, so it is no surprise that we have seen a number of innovations aimed at making life quieter. These include sound-absorbing chairs for offices and noise reducing acoustic panels made from wool.
Written By: Lisa Magloff