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.
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.