>Now, take the headphones away then think about what you have to do to cancel noise. You have this two dimensional window in your home that lets through three dimensional sound waves. The best that you can manage is a two dimensional speaker array which is what you see there attempting to create some sort of sound hologram.
First, what you be the problem of creating a three dimension speaker array? Sounds totally feasible...
Second, is that really "the best" that we can do? I've read about a mesh of special design that you can put on your window that still lets you see outside and lets air go through, but cancels certain movement/frequencies, cutting off noise.
You’re right, I should have been more explicit. Passive noise cancellation is far superior for a window. I was trying to point out that active noise cancellation is not feasible (not impossible though) because of the extra dimensions and that the engineering behind active noise cancellation headphones is not the same as what it would take to cover a whole window. By several orders of magnitude.
Honestly, people should just drill an extra hole in their walls, add a quiet fan and put a series of passive sound plates and other known geometry to cancel the sound. Or pipe fresh air from the roof.
First, what you be the problem of creating a three dimension speaker array? Sounds totally feasible...
Second, is that really "the best" that we can do? I've read about a mesh of special design that you can put on your window that still lets you see outside and lets air go through, but cancels certain movement/frequencies, cutting off noise.