21–30 of 31 posts
I always thought the only way of doing this would be to have detached microphones positioned between the speaker and the target noise so the system has enough time to compute the inverse of the incoming waves and send them out with enough space to cancel in the correct phase.
Earlier quoted context omitted.
Yes, and there's whether it actually works IRL. I think it's feasible to have something like the concept, but there are quite a few hiccups along the way -- I'm no audio expert, but I suspect that a single microphone/speaker location may be unable to cancel satisfactorily the incoming sound field through the window. Also, Loud noises creep in through various places, so if your window is quite good already you many no…
I've done quite a bit of signal processing in my day. Audio, image/computer vision, radio comms, etc. This product strikes me as not terribly honest for a few reasons: Geometry The mic/speaker assembly are in the middle of the window but the window has substantial size relative to the dimensions of the room and the distance the listener is from the device. What this means is that you have a multipath problem; the ori…
The mic/speaker assembly are in the middle of the window
but the window has substantial size relative to the
dimensions of the room and the distance the listener is
from the device.
Selective noise cancellation could be possible using a Fourier transform. Zero out the coefficients that you still want to hear and then perform an inverse transform, then a time-domain inversion, and finally apply the appropriate amount of delay to the signal.
You might know this, but I want to state it at least for the benefit of people reading this without much signal processing experience. Just zeroing like that really isn't the best idea. Square waves (that are 1 for signals that you want and 0 for signals you don't want) inverse Fourier transform to sinc functions[1], so if you are filtering just by chopping things out, it will greatly distort the time-domain system b…
Earlier quoted context omitted.
Yes, and there's whether it actually works IRL. I think it's feasible to have something like the concept, but there are quite a few hiccups along the way -- I'm no audio expert, but I suspect that a single microphone/speaker location may be unable to cancel satisfactorily the incoming sound field through the window. Also, Loud noises creep in through various places, so if your window is quite good already you many no…
I've done quite a bit of signal processing in my day. Audio, image/computer vision, radio comms, etc. This product strikes me as not terribly honest for a few reasons: Geometry The mic/speaker assembly are in the middle of the window but the window has substantial size relative to the dimensions of the room and the distance the listener is from the device. What this means is that you have a multipath problem; the ori…
I'm not convinced about the ability to block out certain types of sounds (e.g. birds vs traffic), but blocking out certain frequencies should be quite possible. Of course, there's one question the article didn't address: what proportion of sound is actually transmitted through window panes? One would expect that a whole lot of low-frequency sounds (traffic) would come through the walls too.
I got the impression it would play bird sounds, i.e. a "zen" noise generator, not filter actual bird sounds through.
> With its concentric broadband antenna rings, it harvests the energy of electromagnetic noise from Wi-Fi, and similar signals and this way also reduces the level of e-smog pollution in your environment.
facepalm. This is nonsense.
Really, fellas? I don't mind a discussion on how it could possibly be done, but where's your rudimental critical thinking? Even reddit had a better discussion [1].
[1] http://www.reddit.com/r/gadgets/comments/1pdfb0/volume_knob_...
I just don't believe this concept could work the way the video demonstrates it. Nice interface though... but that's kind of the easy part.
Earlier quoted context omitted.
Yes, this should be on a crowdfunded project asap if the prototype in the video was really functional and no simulated sounds were added. I'd buy it in an instant! Maybe I'll attempt to promote it on Reddit to help with gaining more 'mass-appeal' traction.
I'm pretty sure it was CGI.