@rvpiano
Some people argue that there is no sonic difference with systems being wired out of absolute phase.
But, with music like classical (and a lot of acoustic jazz), where: all the musicians are playing at the same time, in the same acoustic space, and the recording engineer took good efforts to capture the spatial cues, the ambience of the acoustic space, the musicians position within it, etc., there is a definite difference.
And of course, you are pointing out exactly where those differences are: soundstage, imaging, etc.
The human auditory system evolved to be able to discern interaural time differences between our ears as low as 7-10 microseconds. We leverage this ability when we hear soundstage and imaging on our audio systems.
This is what gives us (and our ancestors) the ability to tell if a snapping twig in a forest is in front or behind us, about how far, etc., in case it is a predator.
Our auditory system is better at this when to initial waveform of the noise is rising, not falling. So, when our systems are in correct absolute phase, sounds are rising when they should be, and falling when they should be. And we hear that difference in our audio systems as better imaging and soundstage.
I would guess, that people that don't think there is any difference, are listening to music that was recorded in a studio, with: overdubs, panning, delay, use of multiple mono mics on each instrument, etc. So, any hope of hearing natural spatial cues, has been masked by all the studio effects.
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