Just wondered if any tech geeks out there had some noise cancelling headphones they were willing to cannibalise.

I figured you could utilise the output via the aux stereo input to actively quieten the cabin.

Of course you could use a simple microphone/preamp combo wired out of phase but you'd need some sort of processing to alleviate feedback.

Just a thought for any electronics wizards out there.

I'd be interested to hear how you get on - although I'm sceptical about whether you'll have any success.  I've been involved on the edges of this kind of thing for a number of years, and active anti-noise in any kind of space takes a lot of power, both audio and processing.  You have phase issues which you have to manage throughout the whole cabin, or at the very least target the occupant ear positions.  I've seen particular issues like a single gear whine etc. dealt with for demonstration purposes, but the only active systems I've seen have any success on production vehicles are those that use active devices to cancel vibration at the mounts or suspension inputs, and thereby avoid the noise being generated in the first place.  And those have only ever been on high-end cars.

 

Could be interesting to see if you have any success, though.