yotsuya said:

In listening to the DVD audio to see if I could extract anything better (and failing usually), I think some of the sound effects are syth and could be by Vangelis.

Oh yes, I remember thinking that some of the Esper machine bleeps sounded just like they'd been played on a Yamaha CS80 - actually the four ones heard just before Deckard says "Track 45 left" ("Main Titles", 0:36, 1994 Warner release).

Also, that woosh sound heard many times during the movie. I have heard a version of "Deckard Enters The Bradbury" which has no sound effects but where the woosh sound can be heard during amost of the track. Who knows?

Much has been said about whether the Blade Runner soundtrack is to be appreciated with or without sound effects. I personally think: both ways! but I know many people who are craving for the purity of the original sound-FX free cues only. Maybe it would change slightly the debate if it would appear that Vangelis has played some!

Actually the Master himself did it both ways: while the Trilogy's CD1 (= 1994 album) has sound effects and dialogs from the movie, CD 2 has none...