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William Sommerwerck William Sommerwerck is offline
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Gary, I'm going to explain this one last time. And that's it.

1. There are two recording/playback technologies that are known to more or
less accurately render directionality (and therefore spatiality) -- binaural,
and Ambisonics. (There might be comparably good WFS systems.) These represent
a standard against which other forms of recording and playback can be judged.

2. As someone else pointed out, Michael Gerzon's research into surround
psychoacoustics is the current "reference" for such things. Is it necessarily
complete and correct? Almost certainly not. But he did develop a "meta-theory"
of directional hearing which can be applied to a range of recording and
listening conditions. *

3. All we're interested in is accuracy. (De gustibus, etc.) Anyone is free to
record and/or play back in any way they like, and if they like what they get,
fine. But liking something doesn't mean it's accurate.

4. You can argue all you like, but at some point you have to do the following
things:

a. You have to demonstrate that your playback technology /accurately/
reproduces the original ambient field (at least subjectively).

b. You then have to connect your technology with existing, accepted
theories --
either as extensions of them, or corrections to them.

Once you've done these things, then others will be willing to give your ideas
serious consideration. If you are not working to these ends, then you are
wasting your time and ours.

Please, please, please -- make an effort to understand my e-mail signature.

* I haven't studied the theory, and am blindly accepting the truth of its
validity.

http://decoy.iki.fi/dsound/ambisonic.../data/6827.pdf


"We already know the answers -- we just haven't asked the right questions."
-- Edwin Land

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William Sommerwerck William Sommerwerck is offline
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I've read your response, Gary, and you are not addressing the legitimate
practical and philosophical issues I have raised.

Unless and until you address the question of the accuracy of your proposed
system, it will remain one man's taste, with no reason to be seriously
considered by anyone interested in improving the quality of sound recording
and reproduction.

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William Sommerwerck William Sommerwerck is offline
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PS: I am reminded of someone arguing against Special Relativity, when the fact
is that many experiments have established its general validity.

The argument that the listening room somewhat alters the sound is a red
herring.

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Gary Eickmeier Gary Eickmeier is offline
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William Sommerwerck wrote:
PS: I am reminded of someone arguing against Special Relativity, when
the fact is that many experiments have established its general
validity.
The argument that the listening room somewhat alters the sound is a
red herring.


William -

I directly answered the matter of accuracy in my lengthy response. If it
might help, let me put it one very brief other way.

You record a live concert with the intent and purpose of the facsimile
reproduction of the auditory perspective for a loudspeaker presentation.
There is nothing wrong with your recording techniques, your speakers are the
best in the world.

If, by "accuracy" you mean that it will sound exactly the same as that
larger room that you recorded, then the answer is no, you cannot get there
from here. If you have normal acoustics in the playback room, you will hear
that room superimposed upon what you have recorded. If you kill all or most
of the playback room (read anechoic chamber) it will not sound the same,
won't even sound good.

My conclusion, accuracy is a false goal. Perhaps a further question to ask
ourselves would be "accuracy" of what compared to what? The mistake that
many make with this misleading term is to think that what you want is
accuracy of the output of the speakers to the input signal into "the
microphones." But that is misleading because the recording engineer has not
placed the microphones at the best seat in the house, he has placed them so
that the final result when performed on loudspeakers at some distance in
front of you in another room will sound best.

Perhaps what you are thinking of is accuracy of the original sound to the
playback sound. If so, how do you get there from here? Nearfield monitors?
Ambisonics? Surround sound? I'm afraid it is still going to be elusive,
because our ears require some support of a real playback room to anchor the
sounds and externalize them. I have written about that in the past as well.

So OK, your turn. How do we get there fom here? First, accuracy of what
compared to what. Second, how do we do it. Sorry to be so blunt, but if you
are going to use a term and demand that I address it, you've got to define
it.

Gary


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William Sommerwerck wrote:

I've read your response, Gary, and you are not addressing the legitimate
practical and philosophical issues I have raised.

Unless and until you address the question of the accuracy of your proposed
system, it will remain one man's taste, with no reason to be seriously
considered by anyone interested in improving the quality of sound recording
and reproduction.


The killing floor is now littered with nails with headaches.

Sooner shall pigs yodel than will Gary listen.

--
shut up and play your guitar * HankAlrich.Com
HankandShaidriMusic.Com
YouTube.Com/WalkinayMusic


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Gary Eickmeier wrote:

I directly answered the matter of accuracy in my lengthy response. If it
might help, let me put it one very brief other way.


You can't learn while you're talking. Apparently you aren't equipped to
shut up and listen. This might as well end hilariously, becasue it's not
going to end intelligently.

--
shut up and play your guitar * HankAlrich.Com
HankandShaidriMusic.Com
YouTube.Com/WalkinayMusic
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William Sommerwerck wrote:

Gary, I'm going to explain this one last time. And that's it.


1. There are two recording/playback technologies that are known to
more or less accurately render directionality (and therefore
spatiality) -- binaural, and Ambisonics. (There might be comparably
good WFS systems.) These represent a standard against which other
forms of recording and playback can be judged.


Binaural comes in the category "a recording that fits my system", but not in
the category "a recording that fits all systems" even if the headphone use
requirement is met. It fails 100 percent of the time for me.

Kind regards

Peter Larsen





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William Sommerwerck William Sommerwerck is offline
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One other comment, and I will let this drop...

The idea that the listening room should have a //significant// interaction
with playback has long been abandoned, for the all the obvious reasons.

The only currently acceptable form of interaction that I am aware of is LEDE.
It was developed to //minimize// room coloration from early reflections, while
allowing the creation of ersatz "immersion", without significantly altering
the speakers' direct sound.

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William Sommerwerck wrote:

One other comment, and I will let this drop...

The idea that the listening room should have a //significant// interaction
with playback has long been abandoned, for the all the obvious reasons.

The only currently acceptable form of interaction that I am aware of is LEDE.
It was developed to //minimize// room coloration from early reflections, while
allowing the creation of ersatz "immersion", without significantly altering
the speakers' direct sound.


There are various ways of going about room treatment, and much progress
has been made over the years. All of the successful approaches work to
neutralize spurious room responses.

--
shut up and play your guitar * HankAlrich.Com
HankandShaidriMusic.Com
YouTube.Com/WalkinayMusic
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Scott Dorsey Scott Dorsey is offline
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hank alrich wrote:
William Sommerwerck wrote:

One other comment, and I will let this drop...

The idea that the listening room should have a //significant// interaction
with playback has long been abandoned, for the all the obvious reasons.

The only currently acceptable form of interaction that I am aware of is LEDE.
It was developed to //minimize// room coloration from early reflections, while
allowing the creation of ersatz "immersion", without significantly altering
the speakers' direct sound.


There are various ways of going about room treatment, and much progress
has been made over the years. All of the successful approaches work to
neutralize spurious room responses.


But not to neutralize _all_ room responses.

There was a study recently which I think was done by Vanderkooy, in which
a number of small listening rooms were tested by a listening panel that
thought they were testing different speakers. (In fact all the rooms had
identcal speaker systems.) The perceived quality of the speakers was
directly correlated with how flat the room response was at the listening
position.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."


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Gary Eickmeier Gary Eickmeier is offline
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William Sommerwerck wrote:
One other comment, and I will let this drop...

The idea that the listening room should have a //significant//
interaction with playback has long been abandoned, for the all the
obvious reasons.
The only currently acceptable form of interaction that I am aware of
is LEDE. It was developed to //minimize// room coloration from early
reflections, while allowing the creation of ersatz "immersion",
without significantly altering the speakers' direct sound.


I agree that we should drop it for now. This discussion is beyond what we
might call the "Alrich Barrier" of knowledge about acoustics and
psychoacoustics. All I am trying to tell you is that the live sound has a
complex pattern of direct, early reflected, and reverberant components to
the total sound field. If you reproduce what you have recorded with just the
direct sound from a pair of speakers, any speakers, the reproduction will
sound different from the original and you have got to replace the missing
fields somehow. The sound doesn't just "go into your ears" and you hear the
original. On any playback system, the spatial nature of what was recorded is
changed into the spatial characteristics of that playback system.

Gary


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William Sommerwerck William Sommerwerck is offline
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"Gary Eickmeier" wrote in message ...

All I am trying to tell you is that the live sound has a complex pattern of
direct, early reflected, and reverberant components to the total sound
field. If you reproduce what you have recorded with just the direct sound
from a pair of speakers, any speakers, the reproduction will sound different
from the original and you have got to replace the missing fields somehow.
The sound doesn't just "go into your ears" and you hear the original.


Tell us something we don't know.


On any playback system, the spatial nature of what was recorded is changed
into the spatial characteristics of that playback system.


Not with Ambisonic recording and playback. Not with the use of a hall
synthesizer.

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William Sommerwerck wrote:
"Gary Eickmeier" wrote in message ...

All I am trying to tell you is that the live sound has a complex pattern of
direct, early reflected, and reverberant components to the total sound
field. If you reproduce what you have recorded with just the direct sound
from a pair of speakers, any speakers, the reproduction will sound different
from the original and you have got to replace the missing fields somehow.
The sound doesn't just "go into your ears" and you hear the original.


Tell us something we don't know.

On any playback system, the spatial nature of what was recorded is changed
into the spatial characteristics of that playback system.


Not with Ambisonic recording and playback. Not with the use of a hall
synthesizer.


Really, not with any system. In every case, what you get on playback is
the sum of the effects of the original hall, combined with the effects of
the playback. Consequently, the original recording needs to be drier than
it would be if it were intended for playback in an anechoic chamber. But
not really very much so.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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Scott Dorsey wrote:

William Sommerwerck wrote:
"Gary Eickmeier" wrote in message ...

All I am trying to tell you is that the live sound has a complex
pattern of direct, early reflected, and reverberant components to the
total sound field. If you reproduce what you have recorded with just
the direct sound from a pair of speakers, any speakers, the
reproduction will sound different from the original and you have got to
replace the missing fields somehow. The sound doesn't just "go into
your ears" and you hear the original.


Tell us something we don't know.

On any playback system, the spatial nature of what was recorded is changed
into the spatial characteristics of that playback system.


Not with Ambisonic recording and playback. Not with the use of a hall
synthesizer.


Really, not with any system. In every case, what you get on playback is
the sum of the effects of the original hall, combined with the effects of
the playback. Consequently, the original recording needs to be drier than
it would be if it were intended for playback in an anechoic chamber. But
not really very much so.


I think the BBC did some research into this in mono a long while ago.
They were mainly interested in the point at which the acoustics of the
listening room began to become audible behind those of the original
studio.

I seem to recall they concluded that as long as the listening room had a
shorter reverberation time than the studio, the listener would only be
aware of the studio acoustics. That assumed a listening room with no
obvious vices (i.e. a fairly flat reverberation/frequency curve) and did
not test for any effects on stereo imaging.



One factor we have not touched on (another can of worms) is whether the
whole of a listening room needs to be treated. When using an empty
cloakroom as a temporary control room for a portable recording session,
I found that it was possible to put the monitors (BBC LS3/5As) at the
same level as my ears and only treat the room at that height above the
floor. Luckily, the rows of coat pegs allowed me to hang several
thicknesses of blankets away from the walls at the correct height.

The upper part of the room was undamped and, when I stood up, the sound
quality was vile with no stereo image - but, at the seated listening
position, I found I was able to form quite a good image and ignore the
rest of the room.

I wouldn't recommend this as general good practice, but it does show
that it is possible to get away without elaborate acoustic listening
room treatment in some circumstances.


--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk
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William Sommerwerck William Sommerwerck is offline
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"Adrian Tuddenham" wrote in message
valid.invalid...

I think the BBC did some research into this in mono a long while
ago. They were mainly interested in the point at which the acoustics
of the listening room began to become audible behind those of the
original studio.


I seem to recall they concluded that as long as the listening room
had a shorter reverberation time than the studio, the listener would
only be aware of the studio acoustics. That assumed a listening room
with no obvious vices (i.e. a fairly flat reverberation/frequency curve)
and did not test for any effects on stereo imaging.


This is virtually common sense. I'm glad to hear the BBC researched it.


One factor we have not touched on (another can of worms) is whether
the whole of a listening room needs to be treated. When using an empty
cloakroom as a temporary control room for a portable recording session,
I found that it was possible to put the monitors (BBC LS3/5As) at the
same level as my ears and only treat the room at that height above the
floor. Luckily, the rows of coat pegs allowed me to hang several
thicknesses of blankets away from the walls at the correct height.


The upper part of the room was undamped and, when I stood up, the
sound quality was vile with no stereo image -- but, at the seated
listening position, I found I was able to form quite a good image and
ignore the rest of the room.


I wouldn't recommend this as general good practice, but it does show
that it is possible to get away without elaborate acoustic listening
room treatment in some circumstances.


Around 35 years ago, when I lived in an apartment in Bryn Mawr, I tacked
4'-square panels of 2" Fibreglas (covered with "glass cloth") to the walls at
about ear level. They did a great job suppressing early reflections, while not
wholly deadening the room. However, I remember an evening some guests stopped
by, and a woman had an immediate claustrophobic reaction to the reduced
ambience. (No one else did.) Her reaction was "honest" -- she was unaware of
the sound treatment.

One might think that virtually complete deadening would be desirable when
playing ambient-surround recordings. But I doubt it.



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"William Sommerwerck" wrote in message
...
"Adrian Tuddenham" wrote in message
valid.invalid...

I think the BBC did some research into this in mono a long while
ago. They were mainly interested in the point at which the acoustics
of the listening room began to become audible behind those of the
original studio.


I seem to recall they concluded that as long as the listening room
had a shorter reverberation time than the studio, the listener would
only be aware of the studio acoustics. That assumed a listening room
with no obvious vices (i.e. a fairly flat reverberation/frequency curve)
and did not test for any effects on stereo imaging.


This is virtually common sense. I'm glad to hear the BBC researched it.


One factor we have not touched on (another can of worms) is whether
the whole of a listening room needs to be treated. When using an empty
cloakroom as a temporary control room for a portable recording session,
I found that it was possible to put the monitors (BBC LS3/5As) at the
same level as my ears and only treat the room at that height above the
floor. Luckily, the rows of coat pegs allowed me to hang several
thicknesses of blankets away from the walls at the correct height.


The upper part of the room was undamped and, when I stood up, the
sound quality was vile with no stereo image -- but, at the seated
listening position, I found I was able to form quite a good image and
ignore the rest of the room.


I wouldn't recommend this as general good practice, but it does show
that it is possible to get away without elaborate acoustic listening
room treatment in some circumstances.


Around 35 years ago, when I lived in an apartment in Bryn Mawr, I tacked
4'-square panels of 2" Fibreglas (covered with "glass cloth") to the walls
at about ear level. They did a great job suppressing early reflections,
while not wholly deadening the room. However, I remember an evening some
guests stopped by, and a woman had an immediate claustrophobic reaction to
the reduced ambience. (No one else did.) Her reaction was "honest" -- she
was unaware of the sound treatment.

One might think that virtually complete deadening would be desirable when
playing ambient-surround recordings. But I doubt it.


I am beginning to hear some good statements here now. Some are agreeing that
you will hear some room effects on playhback and that is part of what we
position our mikes for - planning for it to be played in another space at a
distance from you, restaging the event in front of you.

What I am trying to tell you is that I have discovered some ways to USE the
room to advantage in the playback rather than fighting it and making things
worse. Notice that even LEDE uses the room in the live end part of the idea.
I have gone the opposite way and discovered how to use the early reflections
off the front and side walls in a way that brings out, or decodes, the
spatiality contained in the recording. At the same time, you can neutralize
the deleterious effects of a strong reflected component. What a lot of
people are familiar with and therefore critical of is the mis-use of the
early reflections that can indeed "smear" and cluster and stretch individual
images until you come to the wrong conclusion that we need to get rid of
them all.

William, I do agree with some of the Ambisonics theory and intent. I am also
fascinated by Ralph Glasgal's Ambiophonics system - a loudspeaker binaural
system that goes all out. Too bad binaural isn't the Holy Grail, with all of
the kids listening to music on their earbuds and iPods and such.

I am for any creative approach that takes the acoustic realities of the
problem into consideration. Trying to listen to just the recorded signal in
raw form from the front of the speaker boxes in a dead room ignores
everything we have learned about acoustics and what makes a good hall sound
good.

So to answer my own question about accuracy of what compared to what, I
would say this: The paradigm, or model that we should be studying is the
image model of the live sound. You then study the image model of the
reproduction speaker and room interface and try to make them as similar as
possible. The model sees the recording as a new work, created with the
intent and purpose of making it sound as realistic as possible when played
back in another space with full knowledge that this will be the process and
learning how to do that.

This is a very different way of going about it, and reveals some very
surprising conclusions about the whole process, and all I ask is to be taken
seriously and not laughed at and ridiculed before I get off the stage. I
just might have something to say, and I am here to study the recording end
of it and learn from you all how to complete the loop.

For Hank Alrich, please remember this has nothing to do with Bose speakers
or any particular product. The perfect Image Model Projector has yet to be
designed.

Gary Eickmeier


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Adrian Tuddenham wrote:
Scott Dorsey wrote:

Really, not with any system. In every case, what you get on playback is
the sum of the effects of the original hall, combined with the effects of
the playback. Consequently, the original recording needs to be drier than
it would be if it were intended for playback in an anechoic chamber. But
not really very much so.


I think the BBC did some research into this in mono a long while ago.
They were mainly interested in the point at which the acoustics of the
listening room began to become audible behind those of the original
studio.


I would like to see that research! It's a lot simpler in mono than it is
in stereo, but it would certainly be worthwhile.

I seem to recall they concluded that as long as the listening room had a
shorter reverberation time than the studio, the listener would only be
aware of the studio acoustics. That assumed a listening room with no
obvious vices (i.e. a fairly flat reverberation/frequency curve) and did
not test for any effects on stereo imaging.


Makes good sense in that situation.

One factor we have not touched on (another can of worms) is whether the
whole of a listening room needs to be treated. When using an empty
cloakroom as a temporary control room for a portable recording session,
I found that it was possible to put the monitors (BBC LS3/5As) at the
same level as my ears and only treat the room at that height above the
floor. Luckily, the rows of coat pegs allowed me to hang several
thicknesses of blankets away from the walls at the correct height.


This was because you didn't have any low frequencies to contend with,
so you only really had to worry about direct high frequency reflections.
If you'd been using more full-range loudspeakers you would have noticed
more of a problem.

In the case of direct slapback issues, and this might have been one also,
you really only need to deal with the surface that is causing the slapback.

I am of the mind that a room can be too dead as well as too live, and
that the worst possible room is one that is too dead in some frequencies
and too live in others (as was often popular in the seventies).
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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Scott Dorsey wrote:

[...]akes good sense in that situation.

One factor we have not touched on (another can of worms) is whether the
whole of a listening room needs to be treated. When using an empty
cloakroom as a temporary control room for a portable recording session,
I found that it was possible to put the monitors (BBC LS3/5As) at the
same level as my ears and only treat the room at that height above the
floor. Luckily, the rows of coat pegs allowed me to hang several
thicknesses of blankets away from the walls at the correct height.


This was because you didn't have any low frequencies to contend with,
so you only really had to worry about direct high frequency reflections.
If you'd been using more full-range loudspeakers you would have noticed
more of a problem.


The LS3/5As aren't bad for their size at moderately low frequencies, but
I was recording a wind quintette, the lowest instrument of which was a
bass clarinet and most of its output was harmonics. If I need more
bass, I usually take along my big monitors (1 cwt each), but in this
venue there would have been no room left for me in the cloakroom. :-)


--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk
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Roy W. Rising wrote:
(Scott Dorsey) wrote:

I am of the mind that a room can be too dead as well as too live, and
that the worst possible room is one that is too dead in some frequencies
and too live in others (as was often popular in the seventies).


Sometime before the seventies, a manager asked my thoughts on room
acoustics. I said, "Start out dead, and work your way back from there".
Someone dubbed this "The Lazarus Approach". I guess it still applies.


I am not sure you can do this if you're worried about the low end (which
you might not be for a lot of studio applications like radio announce
rooms). The meadow is nice and dry-sounding but as soon as you put a
wall up, you've got low frequency reflections.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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Briefly, Gary...

The idea that the room should interact with the playback was pretty much
abandoned with the introduction of consumer stereo playback. (I'm not sure it
was ever taken seriously even in the days of mono.) It is a fundamentally
impractical idea, because you are stuck with whatever room you have. And even
assuming an "ideal" image projector could be built, it would be horribly
expensive, as it would require far more high-quality drivers than a
conventional speaker system.

As for "decoding" the ambience in the recording... This has been known for
decades. The brain doesn't do a good job of localizing uncorrelated sounds. If
the program is delayed about 15ms and played through speakers to the sides,
the random-phase ambient components become sufficiently decorrelated that they
are heard as an enveloping ambience. The direct sounds are not random-phase,
and are still within the fusion region, so they still appear to come from the
front.

It's assumed that this "precedence" or "Haas" effect contributes to the
usefulness of hall synthesizers.

https://en.wikipedia.org/wiki/Preced...cement_systems

It's unfortunate you're wasting so much time and money on what appears to be
absolutely useless research, when you could be having a lot more fun listening
to a properly configured surround system. When I play a surround SACD, or use
a hall synthesizer, I get little, if any, sense that I'm hearing the ambient
acoustics of my (untreated) room.

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William Sommerwerck wrote:
Briefly, Gary...

The idea that the room should interact with the playback was pretty much
abandoned with the introduction of consumer stereo playback. (I'm not sure it
was ever taken seriously even in the days of mono.) It is a fundamentally
impractical idea, because you are stuck with whatever room you have. And even
assuming an "ideal" image projector could be built, it would be horribly
expensive, as it would require far more high-quality drivers than a
conventional speaker system.


The thing is, you _can't_ totally eliminate room effects. It would be nice
if you could, but you can't.

So, you're stuck with some room effects, and if properly done those room
effects can be used to improve stereo imaging. The whole LEDE thing is
a very good example of how an improved sense of space can result from
playback room reflections.

But... the room reflections should never be dominant and should never
overpower the ambience present in the original recording.

And no... you _aren't_ stuck with whatever room you have. If you want
an accurate playback system, the room needs to be designed with controlled
acoustics and the speaker system needs to be designed into the room.

But total elimination of room effects is possible to do, and if you ever
listen to playback in an anechoic chamber it is quite interesting but
not necessarily accurate or useful.

As for "decoding" the ambience in the recording... This has been known for
decades. The brain doesn't do a good job of localizing uncorrelated sounds. If
the program is delayed about 15ms and played through speakers to the sides,
the random-phase ambient components become sufficiently decorrelated that they
are heard as an enveloping ambience. The direct sounds are not random-phase,
and are still within the fusion region, so they still appear to come from the
front.


I'll point out that the inability to corellate position of sounds widely
separated in time is ALSO what makes widely spaced omni recordings work. The
brain is unable to make anything of the phase differences and so all the
imaging is the result only of intensity differences.

It's unfortunate you're wasting so much time and money on what appears to be
absolutely useless research, when you could be having a lot more fun listening
to a properly configured surround system. When I play a surround SACD, or use
a hall synthesizer, I get little, if any, sense that I'm hearing the ambient
acoustics of my (untreated) room.


Many of these systems work well when your head is pointed forward, but
come apart when you turn your head to the side. Admittedly, that does
not seem too severe a drawback, especially for sound-for-film.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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"Scott Dorsey" wrote in message ...
William Sommerwerck wrote:

And no... you _aren't_ stuck with whatever room you have. If you
want an accurate playback system, the room needs to be designed
with controlled acoustics and the speaker system needs to be
designed into the room.


I was thinking in terms of the sorts of things Gary wants to do.


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"Scott Dorsey" wrote in message
...
William Sommerwerck wrote:
"Scott Dorsey" wrote in message ...
William Sommerwerck wrote:

And no... you _aren't_ stuck with whatever room you have. If you
want an accurate playback system, the room needs to be designed
with controlled acoustics and the speaker system needs to be
designed into the room.


I was thinking in terms of the sorts of things Gary wants to do.


Gary wants to _replace_ directional cues in the original recording with
dominant directional cues in playback, effectively swamping the acoustics
of the original recording.

That makes for a system that tends to make all recordings sound the same,
whether they are recorded in a dry or wet acoustic.

Some folks in the high end world like the "huge sound" and they want
everything to sound huge, even intimate solo classical and folk
recordings.

I suppose that's nice for them if they like that, but such systems are not
accurate, and it's not possible to make recordings for which they _are_
accurate because they can reproduce only one kind of space. Which also
makes such systems worthless for monitoring work.

But if people like the way that stuff sounds, I'm not going to tell them
not to like it. I'm just going to tell them that making claims of realism
and accuracy of imaging are foolish.


NO.

No Scott, and no William. Your fanciful descriptions of my system are not
what is happening at all.

William has agreed that delayed and spatially separated versions of the
sound can decode the ambience contained in the recording. Scott has agreed
that you always have and need the room on playback because our ears need to
anchor the sound and externalize it. Where you both go astray is when you
think that this process swamps the recorded acoustic and makes all
recordings sound the same. The answer is no, the reflected sound is still
within the fusion time and is still correlated with the direct sound. If I
play a very dry recording, it sounds that way. If I play a wet, or
reverberant recording, it widens out and deepens accordingly, something that
doesn't happen with direct firing speakers alone.

I could say the same thing about listening on Scott's LEDE system. The
spatial nature of his playback situation is just as constant as mine. As for
systems which intentionally do NOT encourage any reflected sounds, all
recordings are heard as the direct only, and so they all sound the same -
everything coming from those two **** holes in the snow - as it were.

My room is very carefully designed for image modeling. The front third or so
is specular reflective to keep the freq response of the image, or virtual
speakers, the same as the primary ones. Imagine listening to not just two
speakers, but a lattice of 8 speakers spread out some distance deeper and
wider than the actual room. Speaker positioning is such that all of these
real and virtual speakers are equidistant from each other. This makes for a
very even spread of the imaging all across the front of your room, not just
speaker to speaker.

As you go back in the room there is more and more absorption and diffusion,
in order to prevent all modes from coming back to the front. You need two
reflective surfaces for slap echo or excessive reverberation - of which
there is very little in a home sized room anyway.

Sound images form themselves in 3D space within the aforementioned lattice
of speaker images. This causes the speakers to disappear and the performers
to seem to be right there in the room in front of you. For live, reverberant
recordings the spread of these reflections is all important in making the
model - your room - take on the characteristics of the recorded space. This
is not speculation, I am doing it ahd have been for like 25 years in my 20 x
30 dedicated room.

William, for the record I don't believe in adding some phony "hall effect"
from a processor. I like to hear only what is contained in the recording,
for better or for worse. I have very few bad recordings, my system sounding
great on most - but not all. If you cannot say the same, you have some
problems in your system that need to be addressed. Some recordings are just
a blast, and I feel sorry for those iconoclasts that are just listening to a
pair of direct speakers with all room sound cloaked. You just don't know
what you are missing.

Gary


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"Gary Eickmeier" wrote in message ...

William, for the record I don't believe in adding some phony "hall effect"
from a processor. I like to hear only what is contained in the recording,
for better or for worse.


Then demonstrate that your system actually does what is claimed for it.

I should add that both the JVC and Yamaha synthesizers use models based on
actual halls. Furthermore, they work with any kind of recording, including.


I have very few bad recordings, my system sounding

great on most - but not all. If you cannot say the same, you have some
problems in your system that need to be addressed. Some recordings are just
a blast, and I feel sorry for those iconoclasts that are just listening to a
pair of direct speakers with all room sound cloaked. You just don't know
what you are missing.

Not much.

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William Sommerwerck wrote:
"Gary Eickmeier" wrote in message ...

William, for the record I don't believe in adding some phony "hall effect"
from a processor. I like to hear only what is contained in the recording,
for better or for worse.


Then demonstrate that your system actually does what is claimed for it.

I should add that both the JVC and Yamaha synthesizers use models based on
actual halls. Furthermore, they work with any kind of recording, including.


The argument is that you can't actually do a real hall simulation unless
you have directional information about the complete wavefront coming from
the sound source. You have some of that, but not necessarily enough to do
a transparent job, and you're starting out with a recording that isn't
designed to be played back that way.

So my inclination to say that hall simulators are as misguided as the
Bose 901, for the same reason, that assumptions have to be made about the
sound source, and that the added ambience is not necessarily accurate.
However, the hall simulators are much more adjustable.

If you _must_ have rear ambience, there is always 5.1 these days. It's
not perfect surround but it's better than the alternatives presented in
this thread, because you're able to emulate the sound heard in the control
booth pretty well if nothing else.
--scott


--
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"Scott Dorsey" wrote in message ...

So my inclination to say that hall simulators are as misguided as the
Bose 901, for the same reason, that assumptions have to be made
about the sound source, and that the added ambience is not necessarily
accurate. However, the hall simulators are much more adjustable.


That's the point, of course. The idea is to adjust the simulator to
approximate the sound of the recording. Neither the JVC nor Yamaha sounds
"phony" or artificial.

If you've never heard a proper demonstration, you need to.

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"Scott Dorsey" wrote in message
...
William Sommerwerck wrote:
"Gary Eickmeier" wrote in message ...

William, for the record I don't believe in adding some phony "hall
effect"
from a processor. I like to hear only what is contained in the
recording,
for better or for worse.


Then demonstrate that your system actually does what is claimed for it.

I should add that both the JVC and Yamaha synthesizers use models based on
actual halls. Furthermore, they work with any kind of recording,
including.


The argument is that you can't actually do a real hall simulation unless
you have directional information about the complete wavefront coming from
the sound source. You have some of that, but not necessarily enough to do
a transparent job, and you're starting out with a recording that isn't
designed to be played back that way.

So my inclination to say that hall simulators are as misguided as the
Bose 901, for the same reason, that assumptions have to be made about the
sound source, and that the added ambience is not necessarily accurate.
However, the hall simulators are much more adjustable.

If you _must_ have rear ambience, there is always 5.1 these days. It's
not perfect surround but it's better than the alternatives presented in
this thread, because you're able to emulate the sound heard in the control
booth pretty well if nothing else.
--scott


I of course have 5.1 and listen in surround all the time. That is, DPL II.
Please read a paper by Jeffrey Borish, "An Auditorium Simulator for Home
Use." In it he describes the image model of the typical live sound field,
then suggests doing what I am doing but with extra speakers and delay,
rather than just reflecting the sound normally. Doing it by reflection
duplicates the patterns - spatial patterns - that the typical live field
has, and does it 3 dimensionally such that the spatial pattern changes as
you walk around, just as it does for the different seats in the concert. You
know how mirrors are three dimensional? Works like that. My surround
speakers and DPL II complete the spatial shape of live sound. It's all done
with mirrors, and time delay is the key to this whole operation.

A brief comment on the hall simulator idea - the Philips company in
Eindhoven built a semi anechoic room that had (I forget how many exactly)
over 20 speakers and signal processing to replace the ambience that would be
missing in such a room. That can work, but I think it would be best with
very dry recordings whose ambience can then be brought back in such a room
with processing from a convolved signal captured in the original hall.

It doesn't have to be that complicated though, but you certainly can't
achieve it with just two speakers in a dead room (which I realize you
already know). You use LEDE and Maggies, I use image modeling and 901s.
Basic idea is the same, you are just not addressing the frontal soundstage
part of the ambience modeling.

Gary Eickmeier




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"Gary Eickmeier" wrote in message ...

Please read a paper by Jeffrey Borish, "An Auditorium Simulator
for Home Use."


Can't. I'd have to pay to read it.
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On 10/10/2013 11:16 PM, Gary Eickmeier wrote:
A brief comment on the hall simulator idea - the Philips company in
Eindhoven built a semi anechoic room that had (I forget how many exactly)
over 20 speakers and signal processing to replace the ambience that would be
missing in such a room. That can work, but I think it would be best with
very dry recordings whose ambience can then be brought back in such a room
with processing from a convolved signal captured in the original hall.


Lexicon makes such a system, called LARES. It was intended for
installations, but a friend of mine has it installed in his studio in
the Seattle area and it works very well. The room sounds quite good with
the LARES turned off but you can turn it on and change the ambient
characteristics over quite a wide range. Musicians who record without
earphones like playing in more spacious sounding room. But of course it
can't take out what the room sounds like.



--
For a good time, call http://mikeriversaudio.wordpress.com
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On Sun, 6 Oct 2013 06:42:24 -0700, William Sommerwerck wrote
(in article ):

1. There are two recording/playback technologies that are known to more or
less accurately render directionality (and therefore spatiality) -- binaural,


and Ambisonics.
------------------------------snip------------------------------


I think you mean for 2-TRACK RECORDING.

One could make a good argument that 5.1 discrete surround does a far better
and more accurate job, assuming identical speakers and great acoustics.

I don't think either Binaural or Ambisonics have a place in 2013. To me,
there are far better, more practical systems that sound better, if your goal
is to reproduce music recorded in a natural space with real ambience.

I agree with the gist of what you're saying, but I think a lot of this stuff
is academic at this point. The vast audience no longer cares. I'm not
saying the purist classical audience doesn't matter anymore, but it's not a
realistic market anymore in the real world.

--MFW

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"Marc Wielage" wrote in message
.com...
On Sun, 6 Oct 2013 06:42:24 -0700, William Sommerwerck wrote
(in article ):

1. There are two recording/playback technologies that are known to more or
less accurately render directionality (and therefore spatiality) --
binaural,
and Ambisonics.
------------------------------snip------------------------------


I think you mean for 2-TRACK RECORDING.

One could make a good argument that 5.1 discrete surround does a far better
and more accurate job, assuming identical speakers and great acoustics.

I don't think either Binaural or Ambisonics have a place in 2013. To me,
there are far better, more practical systems that sound better, if your goal
is to reproduce music recorded in a natural space with real ambience.

I agree with the gist of what you're saying, but I think a lot of this stuff
is academic at this point. The vast audience no longer cares. I'm not
saying the purist classical audience doesn't matter anymore, but it's not a
realistic market anymore in the real world.

--------------------------------------

I was talking about "acoustical truth", not commercial realities.

5.1 discrete is not "more accurate" than UHJ. Even two-channel Ambisonics
images better, and WXY is better still. It remains the reference not only for
surround recording and playback, but for stereo recording and playback.

The issue of commercializing WXY Ambisonics was argued at length and
ad-nauseum in a surround group I belonged to. There are two major problems.
One is that most listeners -- most recording engineers, for that matter --
have no comprehension of what Ambisonics is supposed to do, and how it works
in practice. The other is that, if you record decoded speaker feeds (easily
done on SACD and Blu-ray), there's no guarantee the listener will hear the
intended effect.

Because Ambisonic recordings accurately render spatiality, they are, like
well-made stereo recordings, sensitive to setup, speaker choice, and room
acoustics. This unhappy fact is the commercial death knell for Ambisonics.

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