Designed to reduce cabin noise further, such as electronic whine. Systems use one or more microphones to pick up noise and use the stereo to introduce an out-of-phase signal from the noise, which has the effect of reducing the noise level.
BMW and Porsche go in the opposite direction and actually amplify the engine noise in some models.
Currently available on select models from Ford, Honda, Infinity. The manufacturing cost is fairly minor if a stereo is already included. It can be quite complex and time-consuming to engineer since the listener position and microphone positions can greatly affect the results.
Hardware implemented with the mid-year 2021 Model S and X and activated with the Dec-2021 software release 2021.44.25.