Say what you will about the Atmos mixes of BJ's catalog, but they are definitely not tossed-off rush jobs just done for earbuds. All the albums with the exception of
The Stranger were mixed by Brad Leigh, who was assistant engineer to Jim Boyer and Phil Ramone at the original sessions. I
interviewed Brad last year and I know that he definitely checks his work on a 7.1.4 speaker setup.
With the exception of "Summer Highland Falls" (which is basically just a stereo mix in front with surround reverb, at least until the horn break in the front heights), I thought it was a solid effort. It's not as extreme as the quad mix, but there's a lot of instrument seperation: acoustic guitars only in the side speakers in "Say Goodbye To Hollywood," backing vocals solidly in the rears in "James," the horn solos in "I've Loved These Days" are in the height speakers, etc. I would think even in 5.1 it should still sound pretty surround-y?
The mix on
Glass Houses is pretty similar. The electric rhythm guitars in the first two tracks are completely isolated in the side speakers (and the synth parts that come in after the chorus in "Sometimes A Fantasy" appear from above, to very cool effect). The piano solo in "You May Be Right" comes entirely from behind. The call-and-response vocal parts in "It's Still Rock 'n' Roll To Me" alternate between the front and side speakers. The dueling guitar solos in "Close To Borderline" are mostly in the height speakers.