Apologies that I've only just seen this thread! Yes, noise cancelling headphones / defenders work on the principle that if you record the ambient noise around you, then invert the signal and produce it within the headphone you get cancellation - so for example if you had a value of '25' at 100Hz, by then producing a level of -25 by phase reversal, put the two together and you obviously get zero. But, add in some modern digital algorithms that recognise speech, and that can be put through as normal.
The security guys we use in the 'pit' in front of stages wear them all the time - they can hear each other through mics clearly but the background noise gets dialled out.
The security guys we use in the 'pit' in front of stages wear them all the time - they can hear each other through mics clearly but the background noise gets dialled out.
