Originally Posted by SoundChex
Perhaps I'm just imagining the worst, but it seems that Neo:X matrix encode+decode process we've heard described allows for the possibility of replacing (say) a 'moderate' LS
-to-L velocity vs. L-to-C-to-R velocity discrepancy with a 'more offensive' LW
-to-L velocity vs. L-to-C-to-R velocity discrepancy through placements of the LW closer than -60° and the L Main wider than -30°...?!
If the soundtrack was mixed in a 5.1 setup, then let's assume that the mixing engineer regulated the panning such that the angular velocity from Ls to L is what he wanted, and from L to C to R was what he wanted.
If the Neo:X wide speakers were placed to bisect the L/Ls included angle, it would be positioned at 70° rather than 60°. That would yield a perfectly uniform angular pan through Ls-Lw-L. If the Lw speakers are at 60°, will the 10° offset hurt the pan? Can a human detect that shift in angular velocity whilst being engrossed in the movie? Will phantom image localization be any better? And considering the wide speakers are off-screen, there can be no visual disparity to alert the viewer.
If one is concerned about all this, then DSX wides are a non-starter, as it takes L-R pans and a) accelerates their rate of trajectory, and b) places the hard L (or R) sounds wider than the screen. In cases where a corresponding on-screen image exists, there will no longer be accurate alignment. And don't forget the level and bass emphasis DSX imparts along the way, further altering the nature of the original source.