Here is a comment regarding the video below:
"It has been known, and well described scientifically, for at least 40 years that high levels of early lateral reflections confuse hearing and should be kept low. However, the conditions in two-channel listening rooms are completely different from concert halls, which is why one should be very careful with comparisons here.
In practice, this means that you should mount absorbers at the first reflection area on the side walls or use textile panels or thick curtains/drapes if you want to optimize your listening room. An area of approx. 0.5-1 m2 is sufficient and in addition it is most important to have good absorption from approx. 1 kHz and up, which is why it is reasonable to have an absorbent thickness of approx. 4 cm. More low-frequency reflections are conveniently handled via equalization."
Edit:
And anyone can try putting up that, i.e. "textile panels or thick curtains/drapes".
If you like it, keep them/it, otherwise you, of course, just take them down.
Just to test on.
The side reflection thing has certainly featured in this discussion.
More by accident than design (acoustically speaking) I inherited pretty complete floor and ceiling treatment (slatted absorber ceiling and acoustically porous tatami floor) but untreated sidewalls that can nonetheless slide away. Of course, an open wall has near perfect absorption of 1 Sabine at all frequencies. So that delivers mixing room dryness (in terms of overall RT60 numbers) but optional side reflection can happen in that context.
Thinking of preceding discussion of Toole, we often see the figure (7.14) showing some subjective speaker ranking in mono vs stereo, but less often the following figure (7.16) with the stereo listening by musical genre:
The discussion that follows is interesting:
Figure 7.16 shows the spatial quality ratings for each of the music selections. They are all different. The choral selection used multiple microphones and the chamber piece employed a Blumlein coincident pair. The listening room reflections are likely to be heavily diluted or masked by the spatial information incorporated into the stereo clas- sical recordings. Nevertheless, there are hints of preferential biases in the distributions, but they are different for the two recordings. The jazz selection revealed lower ratings for the Rega. No explanation for this was found, but there is clearly an interaction with aspects of this specific recording.
In distinct contrast, the pop music selection put the Quad in a position of disfavor. In fact, the subjective ratings in this stereo test are remarkably similar to those seen in monophonic listening (Figure 7.14). Why? Of all the recordings, the pop recording was the only one to have significant amounts of hard-panned, that is, monophonic, sound emerging from the left and right loudspeakers and a hard-panned “double-mono” phantom center image. It is conceivable that listeners reacted to the relative lack of reflected-sound (spatial) accompaniment for these monophonic components of the stereo soundstage. In a stereo mix incorporating substantial reflected sound, as in these classical recordings, listeners would hear more low-correlation sounds (low ICCC) placing the musical instruments in a spatial context. However, close-miked sounds hard panned to left and right, as in many pop/rock and jazz recordings, would be heard from “naked” loudspeakers, with only the listening room to provide a spatial context.
I listen to modern studio-assembled and synthetic music so enjoy presentation of a detailed stereo image or soundstage (but care somewhat less about reproduction of a "live event" in a real acoustic space). For people who find the terminology confusing, stereo image is illustrated nicely in a B&O white paper on their variable dispersion, steerable Beolab 90.
The popular music used by Toole in 1985 as described was pretty primitive stuff. More recently we have complex mixes of carefully placed sonics with virtual size, focus, position etc (achieved via manipulation of azimuth, amplitude, timing/phase, frequency, reverb/echo and so on) and far less L/C/R hard panning.
We can probably make an analogy between the narrow/wide dispersion options of the B&O speaker and the effect of less/more side reflection in the room.
And go further with an analogy between a very live room and the omni dispersion mode. The analogy isn't perfect (I think the schematics understate the envelopment factor and may exaggerate the loss of depth, nor do we have more modern effects placing sounds beyond the speakers laterally) but I think it's sufficiently illustrative to convey the idea.
My guess is that as a headphone guy, Cameron is consciously or otherwise aiming for and happy with a certain sonic character that minimised room reflections to a high degree. He likely goes too far for many people, and his room suits some types of music more and others less.
My listening preferences (and others here who share taste for electronic) leans dry, narrow-ish dispersion, low reflection (but not anechoic) and so on. And because many of those instruments and sounds are highly modified and/or have no analog reference, I'm less worried by some of the peculiar timbral deficiencies of stereo that may benefit from masking reflections, in favour of the stereophonic holographics revealed by better controlled reflections etc. A classical listener will likely lean the other way.
I think the point is that now we have a better understanding of small room acoustics, better reproduction gear, better digital tools and so on so we can select, set up and explore systems+rooms that work for our various requirements.
