[Gary Eickmeier]

"Audio Empire" wrote in message
...

I suppose that depends upon what you are trying to record. If you are
recording a rock-n-roll band, it's fine (since most rock-n-roll
performances can't exist outside of the studio, anyway). It is even
"the correct way" if you are recording a jazz group using the
"traditional" 3-channel mono technique (where the ensemble in broken
up into three groups and the groups are pan-potted right, left, and
center). However, it would be a misnomer to call any multi-miked,
muti-track recording "stereo". It simply isn't ; it is merely
multi-channel monaural sound. And if you think that it is not an
incorrect technique to multi-mike a symphony orchestra, then we are
going to have to agree to disagree, because in my estimation, that
procedure is EVERY KIND OF WRONG!

I can only offer you the Telarc and Mercury three spaced omni technique
which won popular acclaim for a long period of time. So much so that Stan
Lip****z found it important to rail against it in his famous article "Stereo
Microphone Techniques: Are the Purists Wrong?".

http://www.aes.org/e-lib/browse.cfm?elib=11494

I claim in my papers that the spaced omni technique is the more correct, for
reasons pointed out in my stereo theory (Image Model Theory, IMT)

http://www.aes.org/e-lib/browse.cfm?elib=5825

Basically, the three omnis are sampling the sound field at 3 locations in
the concert hall, rather than at one central location as with Stanley's
coincident technique and your ideas. There is no single "perspective" from
which you are supposed to witness the sound; if done properly, you should be
able to move around in your playback room and perceive the sound from
various perspectives, just as live. Note also that the three microphones are
picking up not just direct sound, but the room ambience from the left and
right sides and from the center. To play these recordings properly, you do
NOT want that ambience to come from the direct field of your three front
speakers, but from a wide set of incident angles, modeled after the real
thing, and supplemented by surround speakers on delay. Hence, the importance
of the radiation pattern of the front speakers and a correct mix of direct
and reflected emanating from the speakers, with equi-omni frequency response
and room positioning that also models the playback situation after the live
event..

I still disagree. The "perspective" is the one chosen by the mix
engineer when he assigns instruments or groups of instruments to their
left-to-right positions by pan-potting them into place. For instance
if he is mixing a jazz quartet where the dominant instrumentalist is a
sax, and he pan pots it equally between left and right, then it will
appear in the phantom center channel. He might then pan the drum kit
to the left, the bass to the right, along with the piano. That's the
"perspective" that the mix engineer (and, ostensibly, the producer),
wants.

That is the layout of the instruments that the engineer wants, but you may
be able to move around in your listening room and perceive them from various
perspectives. Doesn't work like a visual 3D image or a binaural audio
recording. My IMT sees the reproduction as a model of the real thing, that
you can move around in, rather than a sort of "window" or portal to another
acoustic space, through which you must sit and listen from a single
perspective.

If you had
the multitrack master, if it was recorded that way, then you could
actually
pipe each mike thru a channel of its own out to a speaker positioned
where
it was and you would have my example.

Certainly you would. And as long as the speaker occupied the same
relative space on the playback side that the original instrument
occupied in the record space, then you would have a fair
representation of the original DIRECT sound field (but none of the
venue's ambience).

Why? Where did it go?

I don't think so. The live sound field is incredibly complex. Each
instrument's sound takes it's own path(s) from the instrument to the
ear. It is also mixed in the air with the other instruments
accompanying it and it is followed by primary and secondary
reflections off of every surface, hard or soft, in the room. How can
one ever decide how many channels is enough to convey all the right
cues for every conceivable mix of instruments in every conceivable
type of venue? I think that just getting two-channel stereo right is
difficult enough (witnessed by the fact that it is so seldom done
correctly) and that's a worthy goal, in and of itself.

You are unnecessarily confusing yourself. All of that "complexity" is being
recorded by the microphones and can be reproduced fairly well - well enough
for musical enjoyment - in a loudspeaker playback situation. We cannot get
all the way there because of the nature of the system (the "central
recording problem" of having to run the sound through two different acoustic
spaces), so we must understand what is happening and the limitations of the
system and what we can hear.

All of this does pertain to the OP's initial question, so I don't feel like
we are hijacking the thread too bad, but I would like to take it to a new
thread with a new tack from my usual line, if you would like to follow me
there.

What can we hear?

Gary Eickmeier