[meilankev]

Jeffrey,

You and I see eye to eye on this subject.  It's nice to know I am not alone when stating these "audio truths" forces me to rain on everyone's parade.  

Kevin

[Ulas]

Given: The sound image of a monophonic source, played through a “perfect” monaural system, is a point source superimposed on the loudspeaker.

Given: The sound image of a monophonic source, played through a “perfect” stereo system, is a point source projected between the speakers.

Given: Most studio-produced, stereo recordings are created from multiple monophonic tracks.

It follows: The sound image of a studio-produced, stereo recording, played through a “perfect” stereo system, consists of multiple point sources arrayed between the speakers.

Given: The aural perception of depth and height comes from the correlation of small variations in amplitude, frequency, and phase in the sound heard by the left and right ears.

It follows: With regard to studio-produced recordings, any perception of height or depth and sound from beyond the speakers is an indication of a mismatch between the two stereo channels in terms of phase and frequency response. In other words, the effects of soundstage are the result of distortion.

[PhilNYC]

It follows: With regard to studio-produced recordings, any perception of height or depth and sound from beyond the speakers is an indication of a mismatch between the two stereo channels in terms of phase and frequency response. In other words, the effects of soundstage are the result of distortion....

I disagree with this regarding depth.  You're assuming that a monophonic source has no "spacial" information.  This is not always the case.  A mono microphone recording sound source  from some distance in a resonant room will capture the reverberation and other spacial information.  An accurate playback of that monophonic track will produce soundstage depth for that particular sound source.  

I agree that "soundstage height" (and image height within that soundstage) is a result of speaker design and its interaction with the room.

And I will also agree that, if only using monophonic recording in the studio, soundstage width will be limited to the width of the speaker placement unless the recording engineer does something with the phasing to create a special effect.  But it is not necessarily the result of distortion at the playback system.

[JoshK]

So then it follows that unless the recording engineer adds a phase effect then results outside of the speaker are distortion effects?

I actually really like the way Ulas presented his argument.  Something a mathematician can follow.     I heard the result said before another way but now I see where they got to their conclusion.

[PhilNYC]

So then it follows that unless the recording engineer adds a phase effect then results outside of the speaker are distortion effects?

This is correct *only* in the case of recordings based on monophonic tracks that are placed into a soundstage via a "pan" in the mixdown.  You can get soundstage/imaging outside the speaker from a sound source recorded by a stereo microphone...

[csero]

Given: The sound image of a monophonic source, played through a “perfect” monaural system, is a point source superimposed on the loudspeaker.

No! Mono played back on a perfect equipment is like your room has a door to the original event.

Given: The sound image of a monophonic source, played through a “perfect” stereo system, is a point source projected between the speakers.

No! Stereo can not be perfect, especially not  for center sources and mono because the comb filtering, interaural crosstalk and false interaural clues.

Given: Most studio-produced, stereo recordings are created from multiple monophonic tracks.

Sadly true, worst case they add reverb to imitate aural sound.

It follows: The sound image of a studio-produced, stereo recording, played through a “perfect” stereo system, consists of multiple point sources arrayed between the speakers.

It is also true to any 2 mic recordings. Sounds outside the stereo speakers are coming from the faults of the recording or playback equipment or room.

Given: The aural perception of depth and height comes from the correlation of small variations in amplitude, frequency, and phase in the sound heard by the left and right ears.

The depth has nothing to do with the number of channels. Depth localization depends on a hazy feeling for absolute loudness, timbre differences with distance, time-of-arrival differences between direct and reflected sound and, if indoors, the ratio of direct to reflected sound.
Height front/back perceprion is mainly depend on the individual HRTF variations of the listener.

It follows: With regard to studio-produced recordings, any perception of height or depth and sound from beyond the speakers is an indication of a mismatch between the two stereo channels in terms of phase and frequency response. In other words, the effects of soundstage are the result of distortion.

 
True, even for minimal miked recordings. See above.

[morricab]

I have heard really good soundstaging at home but a friend of mine with some STAX ELS F81 electrostats was able to achieve with some recordings (there has to be the right ambience in the recording to begin with) literally a wraparound effect.  When we got it locked in we almost couldn't believe it ourselves and had to check to make sure something wasn't wired out of phase (which can create a very diffuse sound).  Of course it wasn't because the main instruments were simply locked in front.  Most impressive and utterly/scarily realistic.  With my system at home I am not only getting left, right, front, back imaging and soundstaging but also a sensation of height.  Part of this comes a bit from the fact that the ribbon is canted a bit (speakers are Apogee Caliper Signatures).  

Now I have heard very few conventional "monopole" box speakers that can create this illusion.  The best non-dipole speaker I heard at doing this was the Thiel CS 3.6.   Also the Wisdom Audio, Pipedreams, and Vandersteen Model 5 are very good for this kind of thing (maybe coherent source and/or line source is necessary??).  I remember the Wilson Benesch speakers also doing a pretty good job (I have heard the Bishop, Act 2 and Discovery all sound superb).  One horn speaker I head that did a nice job of soundstaging was the Odeon Number 32(?).  It also did nearly everything else well.  Speakers like Wilsons and Revels don't seem to do as well in the soundstaging game.  B&W speakers are terrible in this regard IMO.

[BobM]

Imaging, soundstaging, tonality - they all require balance. Some of us NY Ravers heard two exceptional systems this past weekend. One of them had truly great imaging, but wasn't tonally correct. It was built for home theatre, not music per se. The top end was extended and precise, but not natural musically. The home theatre presentation knocked your socks off though with its dramatic dynamics and excitement.

The second system was much warmer than the first, with a natural musical presentation. But the imaging wasn't there yet (it is still under adjustment). It might have actually been a tad warmer than neutral, but that is the more forgiving side in my opinion.

Both were top notch in every way, and very different. Almost all agreed the second, warmer musical system was preferred for 2 channel, despite its lack of precise imaging.

I can extrapolate from this that the tonality is of most importance in the system. Imaging, without tonality is nice and definitely impressive, however for musical enjoyment it is not the end of the statement.

Enjoy,
Bob

[nickspicks]

Kevin,

I'm never really understood why audiophiles in general seem to think that microphones are transparent. They're not. They color the sound. With vocals, microphones are often responsible for the excessive sibilance audiophiles complain about and spend so much time and energy tweaking their systems trying to eliminate. All of the major vocalists of the '50s and '60s had a favorite microphone that they used for all of their studio recordings. Some, like Peggy Lee, had a microphone custom made and tune ...

in terms of vocal mics, true.  lots of coloration.  the classic WWII era LD neumanns ...for example.  everyone and their uncle uses these for vocal mics.  they have tremendous coloration.  but its nice.

other mics, like instrument mics....often have coloration, but here is where you can get mics that atcualy are transparent.  Like a soundfield, or DPAs ..or AKGs.   This brings the tonality of instruments into play, definetely.  I am around a lot of "real' instruments, and I can honestly say that the right mic (if you are shooting for absolute tranparency) can make a convincing reproduction.
I"m a minimalist in this regard.  less is more in terms of signal processing.

[hifitommy]

recorded sound is so widely variable that NO one stance can cover this waterfront.  multitracking is accomplished in many different ways: multiMONO, multiSTEREO, minimalist mic-ing with a stereo pair and rear ambience mics AND spotlight mics on soloists like vocals and guitarists that might not make it in the mix otherwise.

and then there is the creative multichannel mixing that comes NOWHERE near reality.  add sound processing like comp/limiting, gating, etc ad infinitum.  

still, now and again, an accurate recording or semblance of same, makes its way to the consumer.  room ambience and studio room sound, instrument and voice locations can actually be delivered.  with live recordings, the audience can emanate from their normal position, back near the listener.  

all this in stereo and is DOES work better with phase coherent, well set up loudspeakers, good (improved) room acoustics included.  

we are often given a BLOB of sound that could just as well be presented by a mono setup that has speakers aimed at the wall, away from the listener.  

vertical imaging is real and captured within some recordings but greatly affected by the speakers themselves and room acoustics.

mono depth is very evident, not just a point at the speakers.  some instruments were closer and others farther from the mic and sometimes make you wonder if the recording is in stereo.  

tonality and deep bass extension also contribute to imaging, and soundstage.

additionally to all this conjecture, some amateur and professional recordists both do and dont recognize when they have produced exceedingly accurate recordings.  

lets not be so quick to make pronouncements that will prove to be the very fallacy you are attempting to debunk.  experienced listeners have an open mind about most of this subject.

[hifitommy]

recorded sound is so widely variable that NO one stance can cover this waterfront.  multitracking is accomplished in many different ways: multiMONO, multiSTEREO, minimalist mic-ing with a stereo pair and rear ambience mics AND spotlight mics on soloists like vocals and guitarists that might not make it in the mix otherwise.

and then there is the creative multichannel mixing that comes NOWHERE near reality.  add sound processing like comp/limiting, gating, etc ad infinitum.  

still, now and again, an accurate recording or semblance of same, makes its way to the consumer.  room ambience and studio room sound, instrument and voice locations can actually be delivered.  with live recordings, the audience can emanate from their normal position, back near the listener.  

all this in stereo and is DOES work better with phase coherent, well set up loudspeakers, good (improved) room acoustics included.  

we are often given a BLOB of sound that could just as well be presented by a mono setup that has speakers aimed at the wall, away from the listener.  

vertical imaging is real and captured within some recordings but greatly affected by the speakers themselves and room acoustics.

mono depth is very evident, not just a point at the speakers.  some instruments were closer and others farther from the mic and sometimes make you wonder if the recording is in stereo.  

tonality and deep bass extension also contribute to imaging, and soundstage.

additionally to all this conjecture, some amateur and professional recordists both do and dont recognize when they have produced exceedingly accurate recordings.  

lets not be so quick to make pronouncements that will prove to be the very fallacy you are attempting to debunk.  experienced listeners have an open mind about most of this subject.