Active noise suppression.

Active noise suppression.

Fellow Teslaphiles,

Does anyone have thoughts on active noise suppression?

Can this be accomplished by software alone using the built-in microphone as a sensor, the onboard computer to process ambient noise and the sound system for output. Can other sensors (microphones) be interfaced with the existing computer/sound system hardware to accomplish noise suppression (question for the Tesla engineers).

The car is fairly quiet and a unique pleasure to drive (Tesla smile).

It would be great if wind noise could be further silenced.

Love the car,


jbunn | May 18, 2013

Short answer, no.

The larger the space, the more complicated the geometry of the space, and the more variability of the listener position, the harder the problem to solve.

Brian H | May 18, 2013

Everybody with headphones?

mkidding | May 18, 2013

you need to know the exact location of the ears to do the active noise cancelling. I think that means both the driver is not allowed to move his/her head, and everyone else in the car would get 2x noise as a result

Robert22 | May 19, 2013

Let's remember it's a car and not a sleep chamber. I find playing music at 7 or 8 cancels out noise quite effectively.

lph | May 19, 2013

Actually guys, active noise suppression systems are already being used in cars. Bose and others have been doing this for a few years already. Ford, Honda, Buick all have this already on their not so luxury cars.
I dont know what it will take to do this in the model S. The higher the frequency (shorter wave lengths) of the sound to be cancelled, the harder to cancel without exact ear location info so dont expect great results for those higher frequencies although averaging techniques can help here too.

lph | May 19, 2013

I believe (someone please verify) that the ear location position ideally should be known to about 6" if you want to cancell out frequencies of 2000 hz or below. For each doubling of frequency the location should be known half the distance.

Getting Amped Again | May 19, 2013

As @lph points out, it's being done:

Here are some noise spectrum measurements I made using an iPhone app while driving 60 mph on two rough sections of a local highway:

I'd like TM to consider this for future versions of the Model S.

jbunn | May 19, 2013

I believe the purpose and the primary effect of noise suppression in modern cars is to cancel engine noise. Tesla addressed that part.

Roughly a 350 Hz wave is one meter in length. To cancel, we want to generate the reverse wave, or one half meter. About 1.5 feet to where the microphone thinks your head is. Hope I'm reasoning this out correctly.

Even in headphones it's rather tricky, and works better with low frequencies. The higher the frequency, the tighter the tolerance.

Based on Got Amped's diagrams there is quite a bit of noise at 500 hz and below. Hard to say how lound, unless we can compare with some other common sounds and other cars. Can we see more of these in other cars?