ANR. When in use in a typical light single like a 172,
etc., can you hear the engine, or the airflow, or even your passenger
speaking (without benefit of an intercom)?

Yes.

ANR reduces the background noise. Anything different from the
background noise is not reduced (anywhere near as much). And even if it
were, your ear becomes more sensitive because it's no longer assaulted
by the din of the background noise.

Jose
--
The monkey turns the crank and thinks he's making the music.
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