Toyota's silent cabins

Toyota has developed a noise-cancelling system for use inside its cars.

The system works using the same principle as noise-cancelling headphones. Microphones are installed in the car's roof to detect ambient noise in the cabin and speakers then play back an opposing frequency to effectively cancel the noise out.

Toyota says its sound-deadening system will be capable of muting low-speed engine hum and tyre noise.

It will be used on the next generation of the Toyota Crown Hybrid, which is sold in Japan only, but the system could be used on other cars, including Lexus.

Other noise-cancelling systems have been developed in the past, including by Lotus and Mazda.