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SO ... HOW do we measure soundstage???

Justdafactsmaam

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The reflections that occur in the listening environment can't distinguish between the recorded direct sounds and the recorded reverberation tails, it "makes a soup" of everything and treats it all as one single continuously changing sound, but as long as the early reflections are kept under control, the diffuse field of sound the late reflections adds to the equation can add a sensation of envelopment (even if this soup of diffused sound contains a mess of every single sound in the recording, no matter if it happens to be recorded direct sounds or recorded reverberation tails).
Which may sound pleasing but bears very little resemblance to the concert hall experience.
 

Thomas_A

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olieb

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I was talking about added listening room sound to two channel stereo playback of recordings of acoustic music recorded in concert halls
You will have added listening room sound with BACCH too, actually even more room reflections than in stereo (from the extra canceling signals). Only crosstalk (locally at the ear that is) is canceled.
 

Thomas_A

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I was talking about added listening room sound to two channel stereo playback of recordings of acoustic music recorded in concert halls
And how are these normally recorded? And if you want to be transferred to the event, how would the recording be made?
 

goat76

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Which may sound pleasing but bears very little resemblance to the concert hall experience.

Who said it was?

At least I will hear the unaltered direct sound of the recording, which would not be the case if I used a phase alternating filter like BACCH.
 

olieb

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Is the binaural recording the reference?
Good question. There is no reference, only preference.
One could argue that a binaural recording would be the "real thing", but for me that would mean with a copy of my head and ears. The KU100 recordings I know are nowhere near to being there for me.
But these recordings are so rare anyway that they just don't exist for all practical purposes.
And probably most people would not be satisfied with the rather diffuse sound on most seats in most concert halls, no comparison with good stereo recordings.
 

Duke

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The reflections that occur in the listening environment can't distinguish between the recorded direct sounds and the recorded reverberation tails, it "makes a soup" of everything

The in-room reflections of the direct sound are not detrimental as long as they don't arrive too early, but ime it is the reflections of the reverberation tails that can really make the difference if they are presented effectively.

For instance, I've heard the spatial presentation transition from "I'm in a normal room and the soundstage extends a few feet behind the speakers" to "I'm in a huge space and the soundstage extends to about as far away as the musicians would have actually been" when the playback room's package of spatial cues gave way to the recording's package of spatial cues due to a change in speaker placement. No way this perceptual difference could arise from a slight modification of the playback room's signature; the only information available that could have conveyed enormous depth and spaciousness was the reverberation tails on the recording, and the speaker placement change resulted in the venue signature on the recording becoming perceptually dominant.
 
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Justdafactsmaam

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You will have added listening room sound with BACCH too, actually even more room reflections than in stereo (from the extra canceling signals). Only crosstalk (locally at the ear that is) is canceled.
Which is why the ideal application is in a dead room. Something I have been advocating this entire time.

You won’t get more room reflections with the BACCH. It does measure and reduce room reflection cross talk too. But the simpler the cross talk present in the room the more effective the filter
 

Justdafactsmaam

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And how are these normally recorded? And if you want to be transferred to the event, how would the recording be made?
No such a thing as “normal” there are books written on recording techniques for classical recording. But the vast majority of these stereo recordings manage to encode a substantial amount of spatial information.

Ideal recording would be a custom binaural recording
 

Justdafactsmaam

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Who said it was?

At least I will hear the unaltered direct sound of the recording, which would not be the case if I used a phase alternating filter like BACCH.
Again that is plainly factually incorrect and directly the opposite of the reality of what is heard with the BACCH. This is objectively demonstrable and measurable
 

olieb

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The in-room reflections of the direct sound are not detrimental,
I tend to disagree.
The fact that these are quite unavoidable, and that one has got used to accept them and last that they are therefore taken into account during mixing does not make them benign.
In most (professional) listening rooms great care is taken to reduce and manage these because otherwise the sound will not be good.
And But they are helpful to mitigate the stereo comb filtering effects somewhat. EDIT: It's all compromise.
 
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Duke

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I tend to disagree.
The fact that these are quite unavoidable, and that one has got used to accept them and last that they are therefore taken into account during mixing does not make them benign.
In most (professional) listening rooms great care is taken to reduce and manage these because otherwise the sound will not be good.
And they are helpful to mitigate the stereo comb filtering effects somewhat.
I edited my post while you were writing yours, so you didn't see my edit.

Yes it would be nice if we could eliminate reflections of the direct sound on the recording without causing worse problems than we solve. I don't know how to do so.
 

olieb

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I edited my post while you were writing yours, so you didn't see my edit.

Yes it would be nice if we could eliminate reflections of the direct sound on the recording without causing worse problems than we solve. I don't know how to do so.
I see only one way of doing so by means of headphones and binauralization.
There crosstalk can be switched off or attenuated at will. And one can use a reverberation file with as much (or little) reverberation as is preferred.
Makes a great desktop system ;-)
 

slaweks

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My room has an RT 60 bellow 100 milliseconds from about 125 hz on up. In conjunction with the BACCH SP I get an astonishing recreation of the concert hall acoustic space with many classical recordings.

Something that no conventional stereo in even a modestly reverberant room could begin to do.
"My room has an RT 60 bellow 100 milliseconds from about 125 hz on up" I envy you :) Mine is 200-250ms
 

Justdafactsmaam

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"My room has an RT 60 bellow 100 milliseconds from about 125 hz on up" I envy you :) Mine is 200-250ms
Which is quite good. I have put a lot of work into the room. And in a few days I am beginning a major reworking of the room.
 

goat76

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Nonsense. It’s not a sound effect. It removes a sound effect. The effect of speaker cross talk. Something that is not on the recording.

Your statement is very easy to falsify just by giving you a sound example of an old stereo recording, you know one of those old "ping-pong" stereo recordings where everything in the mix was either hard-panned to the left or the right speaker.

In the following file of the original recording, it's easy the hear that all the sounds come from the exact point of each loudspeaker. This is how the recording sounds without any effect added to it.

Original track (30 sec): https://www.dropbox.com/scl/fi/7i6a...-sec.wav?rlkey=duoor29q01zwc51f0lfol1vh0&dl=0


This is the same recording but with the BACCH filter applied (specified for a 30-degree listening triangle). I'm sure you can easily hear that the localization of the channels is now much more diffuse and no longer sounds as distinctly coming from the position of the two loudspeakers. This is of course less accurate to the source, and this will affect all regularly mixed 2-channel recordings in the same inaccurate way, even the ones you may subjectively like this effect on.

Track with uBACCH for a 30-degree listening triangle (30 sec): https://www.dropbox.com/scl/fi/fajd...-sec.wav?rlkey=0ia8tt7qk0mvxf66wxuqwkoww&dl=0

.
 

Justdafactsmaam

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Good question. There is no reference, only preference.
One could argue that a binaural recording would be the "real thing", but for me that would mean with a copy of my head and ears. The KU100 recordings I know are nowhere near to being there for me.
But these recordings are so rare anyway that they just don't exist for all practical purposes.
And probably most people would not be satisfied with the rather diffuse sound on most seats in most concert halls, no comparison with good stereo recordings.
This is a topic unto itself. Like every other approach to recording there is an art to binaural recording
 

olieb

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This is a topic unto itself. Like every other approach to recording there is an art to binaural recording
Sure, everything can be done good or badly, but the problem of listening not with the own ears has little to with that.
I made some fun recordings with in ear microphones. The result was amazing, it was crazy how realistic and even holographic that was. You will hardly get anything near with some dummy head.
I wondered whether my ears are symmetric and switched channels in the replay. The whole room collapsed and everything I heard played at the back of my head. Left me quite surprised.
It is just an individual thing.
 

RayDunzl

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