It sounds like the 35mm stereo mix comes from the Japanese laserdisc, the one with digital audio which was discovered a few years ago. If this is indeed the version I’m thinking of, then it has numerous dropouts throughout the movie and a pretty severe instance of tape distortion during the sunset scene.
For the Despecialized Edition, I put together a corrected version of this track, which eliminates every instance of dropout and distortion by replacing them with segments from Belbucus’ analog capture. I also adjusted the gain of the whole mix so that the dialog is at the same level as in the 1993 version, eliminating any perceived difference in average volume when switching between audio tracks. Looks like it’s too late to include it in this release, but most of the errors probably aren’t very noticeable anyway, so it’s not worth worrying about.
For the sake of clarification about my 5.1 version, it was created using the 1993 mix as a base, while removing all the extra sound effects that weren’t present theatrically and replacing them with segments taken from the 1985 mix, level-matched and EQ’d to blend as closely as possible. It was then upmixed to five channels with Prologic II, and combined with a custom LFE channel containing bass effects for each explosion, spaceship flyby, and other things of that nature. Each individual instance of bass was heavily edited (in level, dynamics, and timing) in order to blend into the rest of the soundtrack. Since the 1993 mix was mostly derived from the 70mm printmaster, the changes I made allow my 5.1 to be considered a close approximation of the original 70mm six-channel mix. Obviously it is not exact, since it does not have the true discrete channels of the original, but it does provide a very similar feel. The surround effects are monaural, the dynamic range is for the most part very similar, and the bass provides a solid foundation for the action which is missing in other versions.
I considered this to be worth trying to reconstruct, since Star Wars was the first movie ever to be made with a dedicated LFE channel, and the only other way to hear such a thing on home video is with the rubbishy special edition mixes. Since it is a reconstructed approximation and not completely a preservation as such, and since the real version was only present on 70mm prints, perhaps it does not really belong in a project that seeks to deliver the experience of watching the film on a 35mm print, whose content is 100% authentic. But if people want to include it in their own derived copies (probably with the branching removed to make authoring easier), I certainly won’t try to stop them. 😉
Anyway, enough of that: since I haven’t been around, I had no idea this project was ready for release. It looks to be quite impressive, and I’m certainly very interested in watching a version that is completely sourced from film and contains no traces of the SE whatsoever. Looking forward to seeing it!