Richard Libertini

Popeye was mixed for a failed Vistasonic system with 4 discrete tracks (L/C/R/S). That mix has never been released on home video in its original form.

The older 5.1 track appearing on older DVD/BD releases sounds excellent. It appears to be a slight upmix of the original mix, only splitting the surrounds and adding LFE. It sounds close to the old analog LaserDisc, which is likely the original mix in a matrixed form.

The 5.1 included on the UHD is a new remix which significantly differs from previous tracks. There are new foley effects all over the place. Music is jarringly spliced in from different sources. Unlike the old 5.1 which had clearly discrete surrounds, the channels surrounds overlap somewhat with the fronts here.

Details on the new mix from Paramount's former head of restoration: https://youtu.be/P-AmjqViJyE?t=788

The 2.0 tracks on all DVDs/BDs are just downmixes of their respective 5.1 mixes.

Samples

Lovely underlying remaster by Criterion and Resillion but encode is sadly low-pass filtered by Pixelogic, and even then, the encode is still less than ideal. Still easily obliterates any prior disc release, but certainly wouldn't hurt to have a UK or German label take a crack at this same master.