Noise-cancelling headphones have been around for a while. They work by detecting sound in microphones in the earcups, and then playing the opposite of that sound so you don't hear it. The thing is, what if you want to hear everything except one?
The selective cancellation headphones would have little clip-on wireless microphones that you clip onto what you want to cancel out (speakers maybe) and send the signal to the headphones. When microphones in the headphones recieve that sound, they cancel it out.
A variation is that it sends the sound to the headphones, so people could talk into the microphone to get through to you if you are wearing noise cancelling headphones.-- -----, Nov 29 2004 Extra cost option: wireless microphones you can clip to people you want to ignore.-- krelnik, Nov 29 2004 Your variation at the end is much more easily accomplished.-- swamilad, Nov 29 2004 What did the idea say? (I had my selective glasses on.)
Seriously, though, + (for the variation, mostly).-- not_only_but_also, Nov 30 2004 Fox News does this for most of you, apparently.-- ConsulFlaminicus, Nov 30 2004 Can headphones be built to cancel repetetive noise, as opposed to "ambient" noise? I'm thinking Mario Bros' theme.-- theircompetitor, Mar 16 2005 It ought to be possible for headphones to recognise many pre-recorded sources of noise (e.g. phone ringers, car alarms, advertisements, Radio 1) through Shazam-type technology and then produce anti-noise in real time. It seems like an obvious thing to do. Is this already a thing?-- EnochLives, Apr 15 2018 random, halfbakery