[Gary Eickmeier]

"ScottW" wrote in message
...
"Gary Eickmeier" wrote in message
...
"Andrew Haley" wrote in message
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What does this theory predict that conventional psychoacoustics does
not? In other words, is it possible to design an experiment which
would show whether the IMP is a superior theory to others?

Andrew.

Sure. Just violate any of the three ingredients of the model. If a
speaker
puts out all direct sound, as most do even today, then the majority of
the
high freqs will be heard from the actual speakers only, limiting the
depth
impression and spaciousness.

I find the most realistic depth and spatial impressions come from cues in
the
recording.
Not from cues imposed on playback by the room and room speaker
interactions.
When I was listening to dipoles (Quad 63s) I used rear wave diffusers
(idea I
took from Sound Labs Sallie) and while the impact was subtle I felt it
clarified
the image and increased spaciousness and depth. Multiple secondary
arrivals
just muddled and tended to flatten the image even when they were
substantially
delayed by distance to the walls.
So I cannot agree that high freqs direct from the speakers contributes to
a
limited depth and spaciousness impression. That is dependent upon the
recording. Some recordings will benefit from a direct approach with room
effects minimized while others may benefit from your approach.

ScottW

But don't you get the impression also that the soundstage is limited to
speaker to speaker in such a setup? There seems to be two schools of thought
in playback techniques. There is the let's hear the speakers only and
eliminate the room school, and the float a huge soundstage by means of
reflection from nearby surfaces school.

I say that in all cases what we hear is the presentation in front of us, and
that whatever you are doing with your speakers and room, that is what you
will change the recorded presentation to. In other words, simplest example,
play it back on a boombox with 10 inches separation and that is what you
will hear - it will sound like it is coming from a boombox, not from
Nashville. Play it on some Wilson WAMMs, and it will sound like big speakers
with a lot of bass and whatever the separation of the speakers is. Play it
on some Quads or Maggies or Martin Logans, and it will expand to fill the
front of the room in a larger soundstage with greater depth and out of
speaker imaging.

That is what I hear. On the more direct firing speakers in a dead room, to
me it sounds like the sound is coming from those two boxes rather than a
larger space. The left and right images collect at the speaker grills and ai
lose all suspension of disbelief.

I don't know of any way around all that except an entirely different system
known as binaural, in which each ear is fed its own signal with the
intention of fooling them into being in the original space. But try and do
that with normal stereo and legacy recordings and normal interaural
crosstalk, and your ears will not be fooled, they will hear whatever the
spatial qualities of your presentation happen to be. The sound will be heard
to be coming from where it IS coming, and little you can do about it except
change those spatial qualities to something more like the real thing.

And so my Image Model Theory. The "image model" of the sound presentation in
front of us is the umbrella explanation of all of the above spatial
qualities that we can hear. So I am saying that the object is to make the
image model of the playback as close to that of the live event as possible.
Take two channels, add a dose of direct sound, mix well with reflected in a
certain pattern, and you've got yerself a soundstage modeled after the live
fields.

It seems to work for me.

Gary Eickmeier