I once had a philosophy professor who casually mentioned to the class that
when we listen to a recorded piece of music, we don't hear the entire
spectrum of the music, but only the outer shell. He explained that when,
for example, a classical symphony is recorded, only the extreme peaks and
valleys of the signal are picked up and when the recording is played back,
because the speakers can only move in one direction at any given moment, you
will only hear these peaks and valleys, and none of the filler in-between.
I know that I'm not explaining this using proper audio terminology, but his
explanation seems logical to me. If, for example, a clarinet and a flute
are playing at the same time, all we will ever hear from the recording is
the "combined" signal.

The result of this is that, no matter how good the recording is, we can
never truly hear the individual instruments which, of course, negates things
like "air" around the instruments (unless, of course, there is a space
between the actual notes). In fact, we can never hear the entire orchestra,
nor differentiate between the instruments playing. All we hear is the
shadow of the music.

If this idea is way off, please correct me. I have very little technical
knowledge, but I do love music. Any help would be greatly appreciated.

Roland Goetz.