Toyota Puts the Kibosh on Noise

There’s nothing that speaks of quality and refinement like silence. Besides adding noise deadening insulation, and better, smoother engines, automakers have created a variety of technologies and noise-deadening materials such as QuietSteel to counter unwanted sound. But the latest trend is to reduce noise using sound waves.

Toyota has just announced a new system on its domestically marketed Crown Hybrid which creates antiphase waves, the symmetric opposite wavelength that, when produced, counters specified noise, preventing it from being heard. The system uses a series of three microphones mounted around the cabin that pick up engine noise; combined with a processor that is capable of analyzing sound waves, the antiphase wave is produced and sent through speakers in the front doors and the rear subwoofer.

The important thing about antiphase waves is that they are undetectable to the human ear. Also, the positioning of the speakers ensures that human voices and music aren’t removed. The system is remarkably effective; it’s capable of reducing cabin noise between 5 and 8 decibels. Applied to a high end Lexus, and it is quite possible that Toyota just might have the quietest vehicle ever made.

Several automakers have developed noise cancellation systems including Lotus and Mazda, but the one brand that’s made consistent use of the technology is Honda. Since the launch of its Accord Hybrid, it has featured an active noise cancellation system developed to counteract the sound of its cylinder deactivation-equipped V6s.

Expect this new system to be featured on more Toyota and Lexus products as a way of reducing noise without resorting to heavy sound deadening insulation.