Peter Wieck wrote:
Hello again Peter -
Without re-quoting your entire post -
So, I remain fascinated by the potential in _any_ new speaker design.
You may be selling your design short by dismissing 'less than ideal'
conditions
out-of-hand, and I think you should also question authority and do
some genuine experimentation under those less than ideal situations.
I have found in over 40 years around this hobby that well-designed
speakers are remarkably forgiving of bad situations, whereas marginal
designs fall flat if outside their comfort zone. This remains a hobby
of discovery for me - I switch stuff around and ring the changes on a
more-or-less weekly basis - there are five (5) active systems shared
between this house and the summer house with the makings of several
others going in and out on a regular basis.
Peter Wieck
Melrose Park, PA
Yes, wow - question authority - the story of my audio life. There are some
who agree with most of what I have said about stereo, but more of them
disagree and want the direct sound only theory. Your arguments against the
sweet spot type of speaker are spot on - so to speak. We have this problem
simply because of a side issue of using just two speakers for stereo in the
beginning, but that is not an "essential" part of stereo theory.
I have used the analogy of using a single microphone and speaker for each
instrument in an ideal system. You mike them relatively closely, then play
each channel on speakers with a radiation pattern that is similar to the
instrument it is reproducing, and all placed in positions that are
geometrically similar to where the instrumnts were, in a performing space
that has good acoustics, not a Sonex plastered goofball audio room. You
would have ultimate realism because the system IS REAL and is playing the
performance with the same sound patterns in the room as there were
originally, there is no sweet spot, you can walk around in the room and get
different perspectives on the players, everything with ultimate realism.
Something like a player piano playing back the exact same notes and strokes
as the original on the same instrument in the same room.
That is the root basic idea of a field-type system such as stereophonic
(including surround sound). Two speaker stereo is just a simplification of
such a system, pared down to as few channels as you can get away with and
still have auditory perspective. BUT THEN, the fact that we have only two
ears causes this great confusion about the fundamental nature of the system,
that it is a two ears - two speakers system, with the sound from each
channel shooting into your ears and fooling you into hearing stereo. NO -
the summing localization that is at work is a wonderful effect, enabling us
to use just the two speakers, but it is not a fundamental reason, or
explanation, of how stereo should be done.
With that realization, you jump back to reality and legacy two channel
recordings and ask yourself, OK so how should we be doing this speaker and
room stuff? The answer is that we need to consider the spatial nature of
live sound and try to mimic that in the playback. The speakers, then, rather
than seen as simple direct radiators become Image Model Projectors, using a
combination of direct and reflected sound to set up sound patterns that are
as much like the live patterns as feasible with just a few channels.
Finally, there is no acoustical free lunch. If and when you realize that you
shouldn't do realistic stereo with two small monitors in a small dead room,
hopefully you can see that the size of the playback room is just as much a
part of the equation as any other factor, a larger room sounding more real
because the size of the model is more like the real thing.
So to summarize, the "sweet spot" problem is a red herring and not a
necessary part of stereo theory, just a side effect of doing it with so few
speakers. You can play music in a non-ideal room or in a car or on a
boombox, but then you don't expect ultimate realism, just pleasant sound and
some aspects of fidelity such as frequency response or loudness.
The world of audio "authority" thinks that the process is one of "accuracy"
which is a great sounding word to an engineer, but is not what we are doing
with a field-type system. They think that if the microphones capture the
original with perfect frequency and phase response etc and the speakers
shoot that same "signal" right back into your ears, you will be done, and
the history of audio research has been a search for greater and greater
accuracy. But as you have said, we are already there with every component
but the speakers. The answer to this seeming quandary is that we are doing
realism, not accuracy. We must study sound fields and the spatial nature of
sound before we can realize the true goal we are all after.
When I see some new miracle speaker from some high end maker that has all of
the drivers on one side of the box, I pull my hair out, which is why I am so
bald. If you ever get down to Florida on vacation or whatever, write an
Email back for directions or look me up in Lakeland.
If you would like to continure this, I love to talk audio and we could take
it up in Email or on the phone. Nobody else has lurked on in here because
most of them have heard my ideas before.
Gary Eickmeier
863-670-0850