Interesting read, thanks for reviving the thread. I'm intrigued by the discussion of the authoring - the copy I found a while back is a DVD-A ISO with no menus at all. It's like someone ripped the original copy and then made a new menu-less disc with DiscWelder or Cirlinca.
The sound quality is excellent, but the surround mix doesn't do much for me. It's mixed exactly the same way as the two Chicago DVD-A's that were released. To my ears, there's nothing actually panned to the rear channels; just elements that sort of 'favor' them (horns, some percussion, backing vocals) but appear in all channels at once. The center channel actually contains the most isolated elements - bass guitar, vocals, and some solos. It's more of an 'immersive' experience compared to the extreme directionality of the quad mix, which is the approach the '70s CBS engineers were forced to take because of the SQ matrix.
"If You Leave Me Now" (5.1):
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"If You Leave Me Now" (4.0)":
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