Interesting - I remember reading somewhere that the 1989 LD was the 70mm sound mix, but I can't remember where I read it. From what you say you're probably right though about it actually being the 35mm version. The 'Close the blast doors' line is not there, but the 'tractor beam is located...' line is there!
I do however have an article where it states that the 1995 faces edition LD (and the definitive collection) was remixed by Ben Burtt from the 70mm sound mix. It also states clearly that he added ina few sound effects. The whooshing of the asteroids, and the laserblast which explodes behind 3PO's head just before they get into the escape pod. Also the explosions of the cameras in the detention block scene has added sounds of glass being smashed. I think it was in the Topps Star Wars monthly from 1997... I'll have to take another look though.
I'm really excited by the prospect of the dual layer discs. Just think, we could have the original versions with three/four different sound tracks reflecting the changes between 35mm 70mm THX etc etc! "The Story of Star Wars" LP is also really useful in hearing different versions of lines and voices. Think this was taken from the mono versions of the film.
To Jimbo: Although I haven't posted here very often, I've been reading the forums for a long time. You seem to enjoy being argumentative and confrontational. Please read the title of this website - www.ORIGINALTRILOGY.com.... this site exists to preserve the original versions! This site is NOT called www.specialeditiontrilogy.com is it! I would appreciate it if you left those of us who love the originals alone! We're not baiting you... why bait us? As has been mentioned, there are plenty of other forums where you can express your love for the prequals or the special editions. But - like I said - perhaps you just get off on being argumentative. Yeah, discussions are great, but petty little childish argumets are not! Please think this over mate before posting again.