Sono is a conceptual gadget to turn windows into sound cancelling filters (similar to noise cancelling headphones). A microphone listens to noise coming in and then a speaker sends out sound waves to cancel the noises that have been set to cancel. In this way they are even cooler than noise cancelling headphones as you can tune the filter to let in birds singing and filter out car alarms, etc.
Very cool, I hope this becomes a gadget we can buy (it is only conceptual now). Read more at Dyson design award site.
Noise canceling works not by blocking sound but by using properties of the wave pattern of sound to send sound waves that add to the existing sound waves to effectively eliminate the sound wave – thus we don’t hear anything. This is know as Active noise control or active noise reduction. It isn’t blocking the noise but adding other sound waves that combine with the noise you want to filter to eliminate the sound wave – it actually doesn’t eliminate it, as countering the sound wave exactly is not likely possible, but it results in a very limited sound.
Active noise reduction is best for low frequency sound (due to the nature of waves – low frequency has longer wave lengths). My guess is this will mean this product has difficulty blocking high frequency sound nearly as well as it will do with low frequency sounds.