I love that album, Linda--bought it, excitedly, when it first came out, and still have it.
After learning that the "Appalachian Spring" portion was reissued a couple of times on CD on the Pro Arte label (only with Ives's "3 Places" swapped out for his 3d Symphony + Copland's "Short Symphony"--although there's a Japanese version that retains the original program), I went searching--and, uh, "found" it. Only the artwork embedded in the FLACs shows a Pro Arte album cover that I can't find a trace of anywhere else--and it features the words "Digital Surround Sound." Only two channels, although I suppose it could be Dolby Surround encoded (or "Circle Surround" or some such); I can't tell, since I don't have PLII anymore. But that wouldn't quite compute, anyway, since the original recording on Sound 80 was, as you point out, digital "direct-to-disc." Any clues?
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