"MiNE 109" wrote in message


As he's redefined "sound" as "signal", I guess he's no longer
connected with audio at all.

http://www.m-w.com/cgi-bin/dictionary

signal:

c : a detectable physical quantity or impulse (as a voltage, current, or
magnetic field strength) by which messages or information can be
transmitted.

Are variations in air pressure a detectable physical quantity or not?