Mind Stretchers
On Thu, 31 May 2012 11:05:01 -0700, Gary Eickmeier wrote
OK as long as we are stretching minds here, permit me to do another
thought experiment - which could easily be a real experiment if we
had time etc.
We will record a singer with one mike, a drum kit with another, a
piano and perhaps a bass, all with their own microphones. They are
playing in a good hall or studio. While recording the piano on the
left side of the room we also catch the early reflected sound from
front and left side wall. Similarly for all the other instruments
and voice. The recording now contains information about both the
direct sound of that performer and some of the reverberant from
near them.
First problem - every mic picks up a different view of the reflections
of the room. The strongest reflections often don't come from objects
near the musical instrument, because on a stage the only such thing
near is the floor and the floor does not give a distinct reflection
because every part of it is a different distance away from the mic and
the instrument. Secondly, floors reflect sound away from the mic and
the instrument because the angle of reflection is the complement of
the angle of incidence.
Far better - close mic the instruments, and also mic the room.
We will play back each channel to a fairly omnidirectional speaker
placed in a position similar to the performer it is reproducing.
The singer, for example, will be a sound image that is nailed in the
center of your room and pulled out from the front wall of the room.
You can now walk all around and magically hear the singer where she
belongs, three dimensionally singing right there in front of you.
Any problems so far?
The biggest problem with this is that while the listener can partially
dereverberate the room, his ability to do so is limited. In many rooms
the many reflections from the omni speakers give you a real mess. Been
there, done that with Ohm F's. The second problem is that listeners
don't want to walk around speakers as a rule. They want to sit in
their favorite seat, so anything you invest or pay for that "walk
around" realism is lost and not appreciated. Most speakers are used in
suboptimal places in suboptimal rooms. This very much favors
directional speakers.
If you have a fairly dead listening room (not a bad idea), the best
you can say is that omni speakers are at least not a serious problem.
Speakers with controlled directivity will still sound at least as
good. Again, I've heard this comparison just lately and Gary knows
where. ;-)
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