Pleasurably better, not measurably better

@pinotnoir - Agree! 

One thing I’ve found very pleasurable is stereo crosstalk cancellation. I love the sound it creates, but find the methods used to achieve it difficult to live with. It tends to be a real "head in a vice" kind of listening experience, often with a divider panel right in my face. I’ve always thought that 2 channel stereo upmixing to more channels could be a better solution, but there’s no easy way to do it cleanly. There are sophisticated methods but I haven’t tried them yet.

Last night I decided to try a rather messy and easy way of turning two channel recordings into three channel playback. The center channel is created by simply summing L+R, the Left channel is mixed as L-R, the Right channel is mixed as R-L. It occurred to me that if these three channels were played through speakers positioned correctly they would produce crosstalk elimination while also allowing sounds from different directions in the sound field to approach the head in roughly the right directions. It works and sounds pretty good, but the more surprising thing was how pleasant it sounded anywhere in the room. I tried setting up the speakers closer or further apart, arranged in a U-shape, or all flat against the wall. Regardless it produced a nice sense of spaciousness on stereo recordings with center panned vocalists and instrumentals staying behind the center speaker no matter where I moved in the room, with a respectable sense of depth. This ain’t accurate. It’s messy. But if you’re not in the sweet spot, or even if you are in the sweet spot, it does make center panned sounds much cleaner as there’s no interference patterns or cross talk on anything panned center, and overall it’s just a downright pleasant arrangement to listen to when you’re sitting off axis or moving around the room.

In some ways, this arrangement is "pleasurably better." 

The effect of your mixing is quite similar to the follwoing speakers placements and wiring suggested by one of the members here (sorry I do not recall his name).  The 1st pair of speakers are wired normally and place close together to simulate your center chaneel.  On the 2nd pair of speakers however, the positive terminals are wired normally but the negative (ground) terminals are wired together.  Due to the phase (polarity) opposition, the R2 will only remits the R-L signal and L2 remits the L-R signal.  I tried this setup and, admitedly, I do not find the sound more pleasing than playing 1st pair of stereo speakers alone with proper placement.  The normal setup will render better imaging and soundstage, etc. 

@holmz "To say that the ears are all different would be like saying that the feel of a block of ice or a hot stove is different because all people “feel” differently."

No... we have glasses or custom lasik to correct for differences in vision, some people even have color blindness, and we all have different hearing profiles. If we all had 20/20 vision and hearing, nobody would need correction. As for old and hot, 32 is 32 and 212 is 212, freezing and boiling.... (and even so, some people wear jackets when it's 70 degree weather, while others are loving it in shorts and t-shirt). But that’s not the same as flat to 20hz when my hearing isn’t flat to 20 hz.​​​​​​... If my hearing rolls off at 12hz, then a speaker that rises at that point might actually sound "flatter" to me, at my point of perception, than one that does not rise to compensate for my ears’ rolloff point.

This is why we have bass and treble controls too... to help compensate not only for our own individual hearing but also for our own personal preferences and purposes. It’s music, for crying out loud! Taste matters. I’ve seen plenty of "technically perfect" performances that were boring, boring to me, anyway. There’s something to be said for heart and soul... immeasurable factors. It doesn’t make sense to say one "should" prefer this or that sound, especially if one is reasonably cognizant of audio. Somebody who tells me I should prefer some speaker instead of one that I actually, in usage in my home, like pleasurably better... well, I can confidently dismiss that person’s opinion in that case.

Saying flat is ideal always reminds me of philosophers who have very neat ideal theories which then bump up against real world experience; I’m oversimplifying, but Kant’s "everybody should be treated as if they were all equally rational" comes to mind, and Rawl’s "social justice" theories, as does Marx’s so-called "scientific" economic theories, however compelling on paper... some universal theory of human experience will never, as far as I can tell, be formulated.

Not to dismiss measurements, I check 'em out myself, but technical measurements of equipment don't dictate the pleasure factor of individual listeners... never have, and, as far as I can tell, never will.  The evidence of this claim can easily be seen by the variety of individual choices sophisticated audiophiles make when it comes to our own preferred speakers, for example, in our homes.  In old school terms, "east coast sound vs. west coast sound,"  ... and on and on.  

@curtdr 

It has been suggested previously that reviewers should have their hearing regularly tested and the results should be published for the benefit of their readers but no one seems very willing to do it.

It has been suggested that many loudspeakers have their treble balance tilted upwards in order to catch the listener's attention during a short demo but another consequence of that could be that such speakers will actually sound better to those reviewers who are experiencing some loss of high frequency hearing.

Such speakers will be almost painful to listen to for those who have good high frequency hearing (16kHz+).

Saying flat is ideal always reminds me of philosophers who have very neat ideal theories which then bump up against real world experience;

Maybe, maybe not.

If what we're interested in is the accuracy of playback then we do want a flat frequency response at the point of delivery.

However, there is no good reason for the listener to then modify the signal to compensate for room acoustics, hearing issues, personal tastes etc.

As you say, 

'This is why we have bass and treble controls too... to help compensate not only for our own individual hearing but also for our own personal preferences and purposes. It’s music, for crying out loud!' Taste matters.

It certainly does.