[Audio Empire]

On Sat, 12 May 2012 18:23:01 -0700, Gary Eickmeier wrote
(in article ):

Audio Empire wrote:

While much of what you say is true, with two channels, there is only a
very narrow range of listening positions where the aural images are in
focus. This has to be. Microphones aren't ears and they don't even ACT
like ears and in fact we don't want them to act like ears, because if
they did, we would have binaural recordings, not stereo recordings.
But they do build-up a snapshot of the performance from a fixed
perspective. It doesn't matter whether this perspective is the result
of some co-incident microphone technique such as M-S or ORTF, or
whether it's the result of widely-spaced omnis, or whether it's a
studio-mixed sound-field made up from the outputs of dozens of
microphones recorded to dozens of separate channels all mixed down to
two. The result, on the listener's end is the same. A fixed
perspective that does not move when the listener moves.

Well, I hope you can see that this "fixed perspective" is a property of the
reproduction and not a basic property of the system. In fact, if you have a
multi-miked recording (which is NOT in incorrect technique in any sense)

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!

then there IS no "perspective" from which the recording was made.

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.

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).

You are right again when you say that the only way around this is to
have a microphone and channel per instrument and a speaker on the
listening end per instrument all arranged exactly where the original
instrument was arranged during the recording process. This would give
the playback a similar image specificity to a real performance. Bell
Labs noted this in their 1933 stereophonic experiments. They started
with one channel per instrument (not recorded, of course, merely
piped-in by hard-wire from another, remote location) and kept reducing
the number of channels (on both ends) until but two remained. They
noted that it was entirely practical to convey the stereophonic
effect with merely two channels, but they also added the caveat that
with two channels, the optimum stereo effect was achieved only at the
point in front of the speakers where the sound-fields from the two
channels intersect.

Yes, again, playback only situation, not systemic. And I thought they ended
up with a three channel system.

Read and Welch ('From Tinfoil to Stereo' C. 1967 Howard Sams & Co.,
Inc.) say that the Bell Labs stereo experiements settled on two
channels.

The movie people are always one step ahead of the pure audio people. You can
see that at least with DD 5.1 surround sound, you can be anywhere in the
audience and perceive the center channel dialog as coming from the center of
the screen.

They use three discrete channels in front , so I suspect they would
get a strong dialog channel in the center.

Stereo theory is constantly confused with binaural theory due to the
widespread use of the two channel system. We've got to shake that off and
start from scratch. I really like your example of the Innersound
electrostatics driving you mad. I had the same reaction to the Acoustats.
The classical theorists would think this an ideal situation,

I can't imagine why. I would think that the ideal would be a broad,
stable stereo image with wide dispersion that would give listeners a
decent stereo image no matter where in the sound field they sat.

if the two channels were "ear signals" meant to be piped to your
ears. All that would be missing would be crosstalk cancellation to
get all the way to binaural and total confusion.

Binaural only works with headphones. Even then it's not perfect. The
binaural miking setup cannot differentiate sounds coming from the dead
front from sounds coming from the dead rear of the "head".

I hope that your listening experience with the curved panel electrostatics
also includes a more natural, realistic sound field generated in your room.
Some listeners (Siegfried Linkwitz among others) realize that the reflected
sound can be a part of the realistic construction of the stereo image, and
in fact should be the same frequency response as the direct sound, not an
accidental byproduct of whatever sound comes off the back of a box speaker.

Well, as with most domestic situations, it is what it is.

The whole theory of stereo is usually taken wrong because of these multiple
errors and misconceptions, and there doesn't seem to be a path out of it,
because of a lot of folklore and a lack of a single theory on exactly what
it is that we are doing with auditory perspective systems. Two channel
stereo is the main culprit, and multichannel is a partial solution, thanks
to the film people.

But can't we short-circuit all the cut and try fumbling and examine the
macro situation and state it once and for all?

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.