If you fly much or work in a loud office, you know that noise-canceling headphones can be a sanity saver. Wouldn’t it be nice if you could just have noise-canceling without the headphones? Apparently, a lot of people think that’s a good idea and funded a project called Muzo. [Electroboom] borrowed one and — mystified how such a device could work — set out to test it. Along the way, in the video below, you can see him do a neat demonstration with two speakers canceling each other in his closet.
Based on [Electroboom’s] tests and the tests from other users, it doesn’t appear that Muzo does much to reduce noise. It might add some noise of its own, but that’s a far cry from what people expected the unit to do.
In theory, the device senses vibrations in a flat surface like a piece of glass or a table top and then vibrates the surface to oppose the noise. At least, that’s one of its modes. It is also supposed to be able to mask sound you make, creating a sort of privacy bubble around the device. It can also generate sleep noises, which — of course — might mask other noise, but won’t cancel it.
While it is a great idea, it is hard to imagine how a device like this could arbitrarily cancel complex sounds for all listeners with just a single device located some distance away. With headphones, the sound beams right into your ears and there is a lot of passive noise blocking, as well. There are other special cases where “in air” noise canceling can work