A380 - little things.

[cee cee]

Thanks for that interesting info, ExXB, I wonder how effective it is and how much the noise varies throughout the cabin.

A quick google puts the engine noise at between 50 to 150Hz, which puts the half-wavelength at 1 to 3m, which will probably cover the width of the cabin. Vertically should be easy, just make the top of the headrest the sweet spot. The only thing I cannot get my head around is how they managed it along the cabin. I guess they are just reducing the noise, not eliminating it, so it may make it a bit easier.

I am not an acoustic engineer, just an EE. The technology itself is not hard to understand, but is hard to implement in a multiple-target and multiple-transmitter scenario. I was checking out a (failed) startup around ten years ago that tried to use the same idea to increase data rate from multiple fixed antennas to multiple separate recipients.

Addendum:
After giving it further thought and looking at the placement of the mics and speakers, I think the left half of the noise cancelling deals with primarily with the noise from the left engine and the right half deals with the right engine. It being a narrow body, single aisle aircraft, the aisle is probably noisier with the noise cancelling than without. ie, the noise is pushed into the aisle. Since passengers are generally seated, especially during the noisier take-offs and landings, it seems to be a good trade-off.