For many people, interior noise is one of the most important factors in choosing a car and has promoted the world’s automotive engineers to develop many noise-deadening materials and techniques in a seemingly relentless pursuit to deliver a vault-like driving experience.
A car’s mechanical bits, the wind and its tires are the three main culprits of cabin noises. If the engine, suspension, and exhaust are working as intended, then you can bet most of the noises come from either the wind or the tires. The easiest way to reduce any noise is with sound-deadening.
The average car already comes with some in strategic places, but there is always areas that can be improved. The most common and simple sound-deadening techniques include filling up body cavities with acoustic foam and gluing tar-like acoustic materials to the inside of vehicle doors. Undercoating also provides a measure of noise protection.
The quest of the world’s prominent automakers to cut down on cabin noise to the lowest levels possible has resulted in a number of innovative new techniques, most notably Active Noise Cancellation (ANC). Active Noise Cancellation is actually not a new concept, but its only recently that its application has become widespread in the automotive industry.
Essentially the same technology behind the Noise Cancelling Headsets sold by BOSE and others — have you ever tuned out a talkative office-mate with your headsets? — ANC cancel out the engine’s noise while you’re driving!
The system uses small microphones installed in key places in the car to pick up unwanted noises and then develops counteracting signals emitted via the car’s audio system to cancel them out. You’re basically removing bad noise with good noise.
In many luxury cars, the result is an eerily-quiet interior that allows music and other audio sources to be enjoyed in the highest fidelity possible. In fact, the gearheads at Holt FIAT of Hurst, a full-service car dealership in Hurst, TX, tell us that ANC is increasingly becoming a must-have in the premium car segment.
You might be surprised to know that in an increasing number of sports cars and sedans, Active Noise Cancellation is sometimes fine-tuned to let in little more exhaust noise. I mean, would you want a car with some performance cred to be dead quiet? Probably not.
As impressive as Active Noise Cancellation is on its own, it’s only when working together with other noise cancellation technology that auto engineers can achieve a truly quiet interior. Buick, for instance, combines ANC with other traditional techniques to form what it calls QuietTuning™ (check out the new Buick LaCrosse), a package that employs high tech sound dampening materials, acoustically laminated windshields, 5mm thick side windows, and several sound frequencies throughout the car’s interior. Even the tires are specifically chosen to minimize cabin noise.
Active Noise Cancellation is impressive and will surely pave a way for newer innovations that will make future car interior quieter than any of us have ever imagined. We can’t wait to see what the automotive industry has in store.