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Very interesting discussion. No disrespect intended... I am new to HTS, coming here primarily for REW information, with a background and interest in film sound post-production.

I found the OPs comments about Toole's paper quite subjective given that I've just spent the last 3-4 months studying in depth Dr. Toole's book "Sound Reproduction: Loudspeakers and Rooms", as well as his various talks, presentations, and papers on the subject (including the subject paper), and I don't consider any of the OPs statements regarding Toole's work to be a fair assessment.

If one has read (and understood) his book, then it would be clear that the OPs assessment of Toole's focus (or lack thereof) is incorrect. I find Toole's research completely relevant to the discussion taking place here, and more than relevant. Granted, I am not familiar with the term "Soundstage & Imaging" or SS&I, nor is Google apparently, finding nothing of relevancy in a search. From what I can gather in these discussions, though, it appears to be a more subjective psychoacoustic approach to setting up your sound, which is perfectly appropriate in many situations, but is more than adequately addressed in both Toole's book AND the subject paper. I found much in Toole's book directly related to Home Theaters and their setup.

However, much of Toole's research does address cinemas simply because cinema is the only industry in sound who has a 'closed' calibration standard (SMPTE 202, the X-curve). However, as he rightly points out, and Ioan Allen confirms, in developing the X-curve 'standard', no real science was done - it was a subjective match that produced the X-curve used by theaters the world over and in every major dub stage where predictable sound from production to presentation is desired. The findings presented in this paper even point out that the standard is often 'subjectively' altered to overcome some of the standard's shortcomings in sound reproduction in theaters.

Contrary to the OPs statements, Toole, in his early days at Harman, pioneered the measurement of off-axis sound from loudspeakers, and notified the industry of their importance in the overall sound-field, in both early and late reflections and in the reverberant sound-field (which really doesn't exist in small rooms). His research goes so much deeper than just placing some unknown speakers in an unknown room, and EQ'ing until it sounds good (the subjective approach, which is not sufficient for critical listening and standardization - more is needed). It's importance is clear when a true understanding of how a fully specified speaker (with complete anechoic data) will react in a particular room, and in being able to predict what a room curve will look like based upon that data before measurements are ever made. This all has very much to do with off-axis sounds.

Finally, it must be understood that the subject paper addresses a specific problem: challenging the standard assumption that a steady-state amplitude response measurement is the best calibration choice, and the one used in cinemas and mixing rooms everywhere. This is only a glimpse of what is known and what has been studied. If you are interested in reading more about how off-axis sound affects what you hear, whether for movies or 'SS&I' (and whether or not good off-axis performance is really that important in certain situations), I would certainly recommend more than a cursory read of Toole's book. I'm a physicist and it took me two full reads, quite a bit of reflection, and several conversations with the author, to fully grasp the content. It's definitely NOT light reading, but I found it quite illuminating.

Cheers,
Shane
 

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Ears are fallible. Imaginations are powerful. Any individually-derived conclusion must be scrutinized relative to proven facts.
It seems that the concept of Sound Stage & Imaging (SS&I) would be a prime candidate to fall within the confines of the assessment process that was described above. Has anyone attempted to do that? If so, what were their results?

It would seem that the audible results of SS&I are heavily influenced by the orientation of the loudspeakers relative to the listening position, and the vagaries of each individual listening room. Until you have a standardized room, it's going to be difficult to assess this parameter, even for high-end listeners. It may be prudent to keep in mind the underlying effects of imagination on the listening experience, or rather, the ability of our brain to create a "stereo image".

[That the] hoped-for "calibration methodology that could be applied throughout the audio industry" (abstract) appears to disregard a critical slice of the high-end listener pie.
It would seem more likely that the opposite is true. The high-end listener is potentially less likely to seek out a standardization of their listening space to obtain consistently reproducible sound quality from one listening room to another. Doing so might serve to reduce the effect of imagination on the SS&I listening experience.
 
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