I have read that Michel Geiss states that there was only ever 1 mix of Equinoxe, yet there are clearly 2 distinctly different sounding versions in exsistence.
The Eminent strings and some VSC sound effects are louder in the 'original' and the mix sounds 'muddier' with some of the other sounds far less prominent.
The other example ( which I first came across on his Essential LP ) sounds like a more sophisticated mix with far more clarity - all the elements seem to have more of their own space within the soundscape.
In the original, nearly everything is panned far to one side with a strong delay bouncing to the opposite - this is not as much the case in the second version.
It sounds to me like a new mix made to take advantage of the then new technology in processing like sophisticated reverbs and enhancers.
But then why would Geiss say otherwise?