Pirelli's noise-canceling tires are a simple solution to a complex problem
With just a strip of open cell foam, Pirelli has found a way to make road tires significantly quieter.
Modern cars make a ton of amazing noises, whether that be intake honk under full acceleration or pops and crackles from the exhaust on engine overrun. One of the sounds they make that isn't so pleasant is tire noise, and with the super low-profile and wide-tread rubber found on luxury and performance cars, tuning that out is an increasingly difficult problem.
One way of cutting road and tire noise in the cabin is to pile layer after layer of insulation and carpet into the vehicle's interior, but this adds weight and cost. Italian tire manufacturer Pirelli found a different solution that reduces tire noise by as much as 3 decibels -- which is a bigger difference than you'd think -- and it's an ingenious one. It's called the Pirelli Noise Canceling System, and it's actually a very straightforward solution.
Because a tire is hollow and filled with air, the air moving around inside from heat and vibration as the tire rolls down the road makes noise. These vibrations are transmitted to the cabin through the vehicle's suspension. Pirelli's solution involves a layer of open cell foam banding inside the tire that helps reduce and absorb these vibrations before they're transferred to the car.
While this tech came out a few years ago, it took a little while for it to be embraced by manufacturers. As of 2017, it was adopted for use on 78 models from various manufacturers, but the demand for quieter cars has seen the number of adoptions double in the last year to more than 150.
Tires with PCNS are marked on their sidewall with a little speaker emblem with a bar through it, so if you ever wondered why your tire had a mute symbol on it, now you know.
