"Marc J. Zeitlin" wrote

According to:

http://www.telex.com/aircraft/produc...ratus50Digital

that's what they do. Never used one - I have no idea how well it
works, if at all. I have a Bose, a Lightspeed 15XL, and a Clarity Aloft.

Which is about what I was saying in my post, back a bit. I thought they all
worked that way, but I learned something new, in this thread.

I did not think that the electronic switching reactions to sound would be
quick enough to cancel a rising sound pressure, as it happens, by applying
an immediate 180 degree out of phase correction. I thought the correction
was applied to the next pulse, as it would happen, if it occurred again.
--
Jim in NC