[Elecraft] Noise Cancelling Headphones

[Ron D'Eau Claire]

True noise cancelling headphones will cut noise far, far beyond anything
acoustic isolation from ear pads can accomplish. 

I have a pair of Audio-Technia QuierPoint ATH-ANC1. They are "on ear" types
so I didn't recommend them to the person asking for ones that cover the
ears. They are very comfortable for me. 

When I fly, as the roar and whine of the big jet engines invades the cabin,
I just switch them on and all the racket becomes a quite background purr.

I often wear them for the entire 11 hours from the west coast of the USA to
Europe, even if I'm not listening to any programs.

The active circuitry in true noise-cancelling phones inverts the sound
arriving and so actually cancels it out. 

The circuit takes a few seconds to adapt so when the attendant brings my
drink she has no trouble waking me. 

73 Ron AC7AC