This is another old lazyweb.org request that I posted and had a lot of interest in. I post it again here because my old blog is now defunct. The end result of this one was “No, it can’t be done.” Basically, the analog to digital to analog conversion that your sound card (and software) would need to do to cancel out the signal can’t be done in real time. If you find something that can approximate this, please do post a comment!
“With a full duplex sound card (capable of playing and recording simultaneously), it seems to me it should be feasible to implement noise cancellation in software on a PC.
Bose has (expensive) headphones that do something like this, if I understand them correctly.
I would like to be able to listen to audio on my laptop and cancel out the sound of the truck parked outside my window. Screaming babies and car alarms would be good test cases as well.
Would that be a wicked Winamp plug-in or what?”