Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "BBC" channel.

I feel contrary. I think Rowan Atkinson is the engineer of humour when it comes to humans and after experimenting enough he has figured it out. His manners appear more like totally calculated instead of natural and by instinct.
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@Patiboke You can use noise cancelling in room, too, but have to install the noise cancelling speaker closer to ear than half the wavelength of the cancelled sound (because the audio waveform from noise cancelling speaker will need to travel through air at the speed of sound and if it's late for more than half a wavelength for given noise, it will be too late and cannot cancel the audio at all). In practice, the noise cancelling speaker must be about 15 cm (~6 in) or less from your head to have any effect around 1000–2000 Hz which is the most accurate part of human hearing. The closer you can get the more complete the noise cancellation can be. Most people do not have desktop speakers this close to their head, so headphones is the only sensible solution. Another option is to install one noise cancelling speaker less than 15 cm from the noise source and try to cancel the audio at the source. This could be done most effectively for low frequencies but speakers able to cancel low frequency noise are pretty big (see a typical subwoofer, and noise cancelling subwoofer would require very small group delay which typically means even more expensive subwoofer).
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@Patiboke Having the noise cancelling speaker near the listener or noise source allows using only one or two microphones per cancelling speaker. but the most important part is ability to react within the time that's shorter than the wavelength of the sound. If you just want to noise cancel a perfectly repeating sound, that can be cancelled more easily because you can be out of sync for the original sound but you can trust that the next loop will repeat the identical sound.
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