Continuing a discussion with Dunedain about the 70mm mix that began in dark_jedi's thread:
hairy_hen: Thanks for the info. :) Since the 93 Definitive Collection laserdisk soundtrack was derived from the real theatrical 70mm soundtrack, plus a few additional effects added, it makes sense to go to a previous theatrical stereo soundtrack (since there's currently no way to access the 70mm soundtrack) and replace those few spots where there were added sounds. And so 70mm "stereo soundtrack" is a good descriptive name for it, since that's what it is, the theatrical 70mm soundtrack down-mixed into stereo form by Lucasfilm for laserdisk.
What is the source for the 35mm stereo soundtrack, a laserdisk set released before the Definitive Collection came out?
The 35mm stereo mix was a high quality analog capture from a laserdisc release from the early 80's, I don't know which exact issue it was (Darth Mallwalker would probably know). If I remember correctly it was the only laserdisc containing that mix that was not time-compressed. Certain parts were replaced from the similar 1985 version when the sound quality suffered and when there were missing frames and so forth. All the work on that was done by Belbucus a few years ago, and he was also responsible for giving us the 1993 Definitive Collection mixes and the mono mix restoration. Without his fantastic contributions to this forum, none of what I did would have been possible.
Note that the fidelity and dynamic range of the 35mm version do not equal that of the DC, and also that the stereo image is noticeably narrower. Because of these discrepancies (particularly the imaging), there are some places where a completely seamless blend of the two sources could not be achieved, at least not with the level of skill I possess. No doubt someone like Belbucus could improve upon it, but it's only a problem if you listen really closely.
In regards to the 1997 SE 5.1 laserdisk soundtrack. One would think that Lucasfilm would have made a more direct transfer of the 70mm theatrical soundtrack this time, since they had 5.1 channels to work with, instead of only 2 in the Definitive Collection. And other than alterations made specifically for the SE, the SE soundtrack should be very close to the 70mm theatrical soundtrack. And since it has discrete channels for all this, it should make for a very nice DD 5.1 soundtrack on DVD. So why not use the 1997 SE as the main source for a recreation of the original 70mm theatrical soundtrack and just replace portions of it with either the 93 DC soundtrack or the 35mm stereo soundtrack where needed to get rid of the 93 DC and 1997 SE soundtrack changes?
There was a time when I would have agreed that the 1997 SE mix would have made a great source for a 5.1 version of the original film. Having heard it now, though, I've completely changed my mind about that--despite its use of discrete channels, the '97 version bears very little resemblance to the 70mm mix whatsoever, even in the parts where there are no added sound effects. Level-matching the '97 and '93 versions to each other, it is immediately apparent that most of the time the dynamic range of the SE mix is at least 3 db lower. In other words, with the average volume of the two coming out the same, the '93 consistently displays significantly higher peak volumes, giving it a much more powerful sound. The EQ is entirely different also, with the SE putting more emphasis on the high frequencies. Not necessarily a bad thing, though to my ear it makes it sound tinny in comparison to the more robust '93 version. Perhaps relating to this EQ, every time C-3PO speaks, there is a huge amount of high frequency noise in the '97 mix--you can hear the noise in earlier versions, but nowhere near that level. (This may have been one of the reasons they remixed the sound for the 2004 dvd; but in that case they went way too far in the other direction, completely killing the highs and pumping up the bass in the sound effects, giving the whole film a distorted, muffled, utterly nasty sound.)
From these kinds of differences, and also the fact that the music in the '97 is consistently more prominent throughout the film than it is in the '93 (I do like that aspect of it), it is quite plain that the SE 5.1 mix was made over again and not derived from the 70mm version at all. On top of all that, there's the issue of the 70mm having a mono surround channel (reasonably well represented when upmixing the '93) and not the split surrounds featured in the special edition. On several occasions the surround effects of the SE become far too loud in relation to the rest of the sound, calling undue attention to themselves; the 70mm by contrast is perfectly balanced in this respect.
Is the .1 LFE channel in the 1997 SE laserdisk set pretty close to what the bass channels in the 70mm theatrical soundtrack sounded like, based on available accounts, did you have to change it much to be more accurate to the 70mm theatrical version?
The LFE channel ended up being the one useable aspect--indeed the special editions are the only home video releases featuring 5.1 mixes, so the bass had to come from there. I mentioned this a few posts up on the page, but I had to do a lot of tweaking to get it to a point of sounding like it actually belonged in the film as opposed to being clumsily pasted on top. Several instances of needlessly loud bass in scenes that didn't warrant their inclusion had to be toned down or removed altogether. Sometimes these overly loud booms came from added CGI shots, in which case even more trickery was sometimes required to integrate them, because the accompanying visuals and main channel sound effects were completely different. Strangely, the iconic Star Destroyer flyby in the beginning did not remotely live up to the "thunderous low end" desired by the original mixers, requiring an enormous boost in volume to sound as powerful as it should.
Mostly I used the 1997 mix for the bass, since for all its defects it still recognisably sounds like Star Wars, and most of the time provided the best match. There were times when I felt the 2004 LFE actually sounded a bit better, so occasionally those were used instead; and a few times neither SE version sounded right, so I ended up deriving the LFE from the existing bass in the 1993 mix. In those cases I had to correct for unwanted phase cancellation with the main channels. Quite a bit of work, really, but worth it, because the resulting 5.1 mix is really awesome. The bass in particular ends up being kind of a 'best guess' on my part--I made it sound the way I think it should, taking into account everything I could find out about the original, and all my observations about the various mixes that have been done over the years.
The links to both the stereo and 5.1 versions are on the first page of the thread. Empire and Jedi are upcoming--not 70mm recreations exactly, because the specifics of those aren't very well known, but they should be of a similar caliber in the overall sound.
Hope that answered all your questions, Dunedain. ;)