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I wonder if it is possible to mount a noise-cancelling device directly on the source of noise, for example, on a circular saw? The frequency of sound waves from a particular tool is pretty predictable and I can imagine a device with a mic or a vibrometer and speakers that clips directly to a tool and suppresses most of noise from this particular source.

I've been using ANC headphones since I started woodworking in the garage and it works for me but not for my neighbours. Soundproofing the garage is difficult and not always possible (not when the door is open anyway), so I would pay top dollar for something like this.

[marcan_42]

It's a soundfield problem. This only works for wavelengths that are larger than the size of the emitters and the distance between them. And even then it only works well if you can get the emission pattern of your cancelling speaker exactly the same as the source.

So, assuming you had a magical beamforming speaker array around your circular saw, you'd still only be able to cancel frequencies around under 1kHz, because there's no way to get the thing in phase above that.

This is why noise-canceling earphones have much better active cancellation at high frequencies than headphones, which rely more on passive isolation until lower frequencies. They're smaller.

[gocartStatue]

theoretically, if the saw has constant RPM then just playing back inverted recording loudly would do it. You just need to match them in phase :)

[kfarr]

Yes I've had a similar idea with a condo neighbor with loud bass, it must be possible to have some attachment you put on the wall to cancel it out. That would sell well