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Info: DC & Faces - Original audio sources (lots of information)

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 (Edited)

I’ve been following the thread in this section titled: “1977 70mm soundtrack recording” with some interest. I thought this might be a good companion piece

There has been ongoing debate for some time surrounding the audio mixes that accompany the “Definitive Collection” and “Faces” Laserdiscs - with regard to Star Wars in particular. Being quite familiar with the 70mm 6-track mix, it was clear to me from the first audition that this was a matrixed foldown of these elements with some additional sweetening – essentially the point of contention. I recently located an old article that clearly details the sources used for these soundtracks and the process of preparing the mixes. I hope to follow up shortly with an audiofile to offer a side-by-side comparison of the ’93 “Definitive Collection” mix and an audience recording of a 70mm engagement. This should further demonstrate the likeness of the two, as well as offer an opportunity to document the additions for those interested.

The following is an excerpt from an interview in Widescreen Review (as seen in issue Number: 5 September/October 1993 - reprinted with permission. To subscribe, please go to www.widescreenreview.com/subscribe.php) with Dave Schnuelle, whose title was Technical Supervisor For THX Software Certification at the time the 1993 Definitive Collection Laserdiscs were produced.

Widescreen Review: What was entailed in producing the soundtracks for The Star Wars Trilogy?

Dave Schnuelle: The people involved with the original soundtracks thought the print masters were in pretty good shape. But in fact when we put up the three print masters and listened to them we were surprised at how limited Star Wars sounded by today’s standards and The Empire Strikes Back was not that much better. And the one that should have been really good, Return of the Jedi, although it sounded better also sounded limited. So when we checked into it a bit more we found that only the two-track, LtRt (left total/right total) print masters that existed were ones that were limited for the capability of the optical sound track with Dolby A-type noise reduction, which means that the peaks were really cut down quite a bit. Thirty-five mm prints with optical sound tracks using Dolby A-type noise reduction only have 6db headroom. So the print masters made for that purpose were all pretty severely limited compared to, say, the six track 70mm print masters. At that point we decided that we would go back and check the original elements. On Return of the Jedi we knew they were all very good, but on the original two we just weren’t sure. In fact the original 6-track 70mm print master for Star Wars and the four-track master mix for The Empire Strikes Back were in good condition for their time and they were unlimited. So we decided then we needed to go back and do each movie over again, making an unlimited LtRt from the original masters.

Widescreen Review: So you used the original print master elements to make a new LtRt 4-2-4 matrixed encoded Dolby Stereo soundtrack master for each film?

Dave Schnuelle: It is interesting in that it really does show changing technology. For Star Wars we had the print master for the 70mm 6-track prints, and an effects-only master. The mixers found by listening that the best way to proceed was to use the four main tracks from the70mm print master, LCRS (left, center, right, surround), for those channels, and to add some low frequency enhancement (boom) from a separate Effects-only master run in sync. The reason to do this was that at the time of Star Wars (for which the “baby boom” format was invented by Steve Katz) what they did to derive the boom channel was to filter out the bass of the complete mix, containing dialogue, music, and effects, and add it back in as the Left Extra and Right Extra channels. The problem with this approach is seen today to be that boom is being added irrespective of its source—and that could include on dialogue where it is definitely unnatural and on music where the music mixer never balanced it in that way. So today mixers would derive the “boom” channel just from the effects, so that is what was done on re-mastering Star Wars. It is really to make the mix come much closer to contemporary standards.
In addition, there were sound effects present in the foreign editions of Star Wars that weren’t in the English-language original. That’s because the English version came out first, and (sound designer) Ben Burtt continued working after that on sound effects as the various foreign versions were made. So for this re-release, Ben came into the studio with a catalogue of sound effects recorded on a Synclavier and literally “spun them in” to the picture while watching it; kind of editing and mixing it simultaneously. Although a tremendous number of effects were not involved, this was Ben’s chance to re-do what he had learned working further on the film and incorporating it back into the “original.” So the laserdisc release really is definitive in the sense that it has in it what the filmmakers wanted to be there.
For The Empire Strikes Back the best material was the four-track master mix. It was supplemented with “boom” from a sound effects master running along in synchronization, in the same manner as Star Wars. What you must realize is that the perceived low-frequency capability of conventional optical sound tracks is very limited, and what most people remember is the 70mm version. Since the existing Dolby Stereo print masters had to be limited for optical, that means that they sound bass shy much of the time, so this addition should be considered to be really a purist one, getting it to sound more like itself.
Return of the Jedi was easier because the thirteen-track mix “stems” were available, so it was simple to make a new, unlimited print master.

Widescreen Review: Who was the mixer for these transfers?

Dave Schnuelle: The mixers on Star Wars were Ben Burtt and Gary Summers. Ben Burtt was not involved with the other two mixes on these discs. Gary re-mastered the other two films. The mixes that are on these discs are all redone directly from the furthest back material that we had and they were all redone directly to digital. Gary produced an open reel DASH format digital audio master, which was then clone-copied to the D1 video master.

Widescreen Review: So there are differences in the Star Wars soundtrack as compared to the older laserdisc releases, but no change in the soundtrack content of the other two films?

Dave Schnuelle: Yes, that’s right, but it doesn’t mean they all sound the same. Tomlinson Holman was the recording engineer on the Jedi soundtrack which was recorded in the first THX Sound System-equipped dubbing stage. So basically I think that even to the relatively untutored ear it is going to be clear that Jedi sounds better than the other two. And that simply has to do with the fact that technology moves along. I think that Gary Summers who was the mixer on all three of these new mixes did the best job he could to make them sound the same. He didn’t degrade Jedi to make it sound like the other two, but he did as much as he could to the other two to get them up to the level of Jedi.

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Thanks for that, belbucus, it provides a real insight into a much discussed topic here. What's most interesting is the description of how the original 70mm 6-track mix for Star Wars was derived from the 4-track master. This is basically what I had assumed, but was unsure of. What it means to me is that the perceived "holy grail" of the 70mm mix is not that at all, and that for home theater, a mix derived from the 4-track master should, in fact be better. Now we know that the '93 mix combined some of each, with additional effects. What I would love to read is a similar explanation about the creation of the '85 mix.
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Having heard the posted recording of the 70mm mix, I arrived at a similar conclusion to that posted by Belbecus--that the '93 mix is, in fact, primarily based on what was used for the 70mm, but with additional sound effects added in. The similarities are too great for it to be anything else. What tipped it off for me was the sound of the wall exploding as the stormtroopers blast their way into the Tantive IV--on the '93, compared to the '85, there is much more bass in the explosion, but it sounds less 'powerful' somehow because of the way the the higher end frequencies are mixed in. The '93 and 70mm are identical in this sound effect, as I had suspected.

Great find, Belbecus!
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All available information would point to a "yes" answer. 1993 transfer, etc.

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Yes, this also shows it is a D1 master, not D2 as some people speculated, which is good news for the DVDs.
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Originally posted by: THX
Yes, this also shows it is a D1 master, not D2 as some people speculated, which is good news for the DVDs.


Why exactly is this good news for the DVDs?

You know of the rebellion against the Empire?

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A little search on the Wikipedia shows us the way:

From D1 article
D1 stored uncompressed digitized component video, encoded at YUV 4:2:2 using the CCIR 601 raster format, along with PCM audio tracks as well as timecode on a 19 mm (3/4") cassette tape. Uncompressed component video uses enormous bandwidth, and a simpler D2 system soon followed.
From D2 article
Like D1, D2 video is uncompressed; however, it saves bandwidth and other costs by sampling a fully-encoded NTSC or PAL composite video signal, and storing it directly to magnetic tape, rather than sampling component video. This is known as digital composite.

I used to be very active on this forum. I’m not really anymore. Sometimes, people still want to get in touch with me about something, and that is great! If that describes you, please email me at [my username]ATgmailDOTcom.

Hi everybody. You’re all awesome. Keep up the good work.

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Yes, basically because D1 is component, D2 composite. So it's good video news (even though this is an audio thread, sorry).
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Upon revisiting this post, I was somewhat puzzled by the response from THX where he states the following:

“What's most interesting is the description of how the original 70mm 6-track mix for Star Wars was derived from the 4-track master. This is basically what I had assumed, but was unsure of. What it means to me is that the perceived "holy grail" of the 70mm mix is not that at all, and that for home theater, a mix derived from the 4-track master should, in fact be better. Now we know that the '93 mix combined some of each, with additional effects.”

I re-read the excerpt and can find this stated nowhere. It seems clearly outlined that the basic track for the ’93 mix comes from the 6-track print master only.

I also disagree with the notion that the 70mm and 35mm sourced a common 4-track master for their respective mixes as has been posted elsewhere (I can think of several comparative examples that demonstrate this). It is my guess that both came from common stems, but that the final mixes of each, reflect different choices in presentation.

I am currently cooking up the side-by-side “93 mix vs. 70mm theatrical” audio file that I mentioned previously. After that, I think a similar “original 70mm vs. original 35mm” would be worthwhile, to explore the issue.
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On "Star Wars" and "Empire Strikes Back" I think, in order to present the two multichannel soundtracks (apiece) as closely as possible to the theatrical originals, they should use the 4-track master mixes. The article didn't mention if the 4-track for ANH still exists, but I would assume it's a major possibility.

Check it out: Both ANH and Empire originally had a 6-track magnetic 70mm Dolby mix and a 2-track matrixed (Lt/Rt) optical 35mm Dolby Stereo mix. The 70mm mix contained 4 discrete channels (Left-Center-Right-Surround transfered from the 4-track) plus "baby boom" (i.e. low frequency effects) on the 2 extra magnetic tracks derived by filtering the bass out from the 4 channels. Correct me if I'm wrong, but it sounds like using the 4-track plus the effects-only master (since home theater setups only use one LFE channel ".1"), both 70mm soundtracks for ANH and Empire can be presented on DVD as a Dolby Digital 4.1 mix. Keep in mind that ANH's and Empire's baby boom content had only mono surround information; "Superman: The Movie" was the first to use split-surrounds (stereo).

Presenting a near-exact copy of the 2-track Dolby Stereo mix would be a bit easier. The 4-track master can simply be matrixed into a new Lt/Rt print as a 2.0 Dolby Surround mix, which upon playback decodes to recreate the 4 channels. During the 80s/90s, "Dolby Surround" was the home consumer marketing name for Dolby Stereo.

Assuming that the 35mm monaural mix (1 optical track) still exists, even easier: simply transfer to a Dolby Digital 1.0 mix. The standard-definition DVD format is well capable of having all 3 soundtracks included. Of course, they would all have to be digitally remastered during these processes as well.

As far as Jedi goes, the article does mention that the 13-track "stems" are available, which can be used to make 2.0, 4.1, or possibly 5.1 mixes.
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You got me there: I was going to write that "Apocalypse Now" was the first to use split surround channels (L-C-R-LS-RS plus one baby boom). That was in the information available at the time of its release. But I looked for a cite and found this on "Apocalypse Now"'s recording sessions:

http://mixonline.com/mag/audio_apocalypse_redux/
The eight-month (yes, this is also probably a record) re-recording schedule resulted in what can certainly be called the first 5.1-channel mix, in that it makes full use of stereo surrounds and low-frequency enhancement. (Although the Dolby 70mm 6-track “split surround” format was developed for Superman in 1978, that film played in less than a handful of such engagements worldwide.)

I don't understand, though, why they say AN "can certainly be called the first 5.1 channel mix" if in the next sentence they say "Superman" played in that format in at least a "handful" of engagements several months earlier. Must be some new definition of "first."

A sound engineer mentions that for "Superman" only two cinemas (one in L.A., one in London) were converted in time to play the new format:
http://hometheaterhifi.com/forum/archive/index.php/t-2897.html

David



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Belbucus, sorry if I phrased my first post confusingly.
Originally posted by: THX
Now we know that the '93 mix combined some of each, with additional effects.
Originally posted by: belbucus
I re-read the excerpt and can find this stated nowhere. It seems clearly outlined that the basic track for the ’93 mix comes from the 6-track print master only. Well, it combined 4 tracks ("some") of the 6-track print master and an effects-only master (which I grant you is not really "some" of the 4-track master in the same sense), with additional effects. Also, when I said:
Originally posted by: THX
What's most interesting is the description of how the original 70mm 6-track mix for Star Wars was derived from the 4-track master. I should have italicized the "how". However, the 6-track mix was indeed derived from a 4-track master, as I think is implied in your original quote:
Originally posted by: belbucus, quoting Dave Schnuelle
...what they did to derive the boom channel was to filter out the bass of the complete mix, containing dialogue, music, and effects, and add it back in as the Left Extra and Right Extra channels. Additionally, here is a quote from a July 1977 article in American Cinematographer by Ioan Allen:

Because of the dual release requirements, six-track 70mm and stereo optical, a four-track master was prepared, carrying left, center, right and surround information. At the end of the mix, the four-track was used to prepare a two-track running master for stereo optical use, and the same four-track was also taken to Todd-AO where it was used to make a six-track running master for 70mm.

The complete article can be found here. Anyway, I appreciate your insights into this and look forward to your comparison audio files.
Originally posted by: scotactor
On "Star Wars" [...], in order to present the two multichannel soundtracks [...] as closely as possible to the theatrical originals, they should use the 4-track master mixes.
Agreed. This is what I meant by:Originally posted by: THX
...for home theater, a mix derived from the 4-track master should, in fact be better.

Originally posted by: scotactor
The article didn't mention if the 4-track for ANH still exists, but I would assume it's a major possibility.
One would hope so, but the article above casts doubt on this, as they settled for the 6-track print master.Originally posted by: scotactor
Correct me if I'm wrong, but it sounds like using the 4-track plus the effects-only master (since home theater setups only use one LFE channel ".1"), both 70mm soundtracks for ANH and Empire can be presented on DVD as a Dolby Digital 4.1 mix.
This is one way a 4.1 mix could be made for SW. Another would be using the 4 tracks of the 6-track print master plus the effects-only master (similar to what was done in '93 but with discrete tracks). Both of these would work reasonably well, but neither would be accurate to the theatrical presentation. A more authentic way to make a 4.1 mix would be to use only the 6-track print master, folding the two "baby boom" tracks into one.

ESB is a different story. The 4-track master mix referred to was used for the 35mm prints. As there are known differences between this and the 70mm mix, it could not form the basis of a 70mm mix reconstruction (regardless of the addition of LFE). Again, a 4.1 mix would best be derived using only a 6-track print master.Originally posted by: scotactor
Presenting a near-exact copy of the 2-track Dolby Stereo mix would be a bit easier. The 4-track master can simply be matrixed into a new Lt/Rt print as a 2.0 Dolby Surround mix, which upon playback decodes to recreate the 4 channels.
Yes and no. While the 4-track masters would likely be the best sources for Dolby stereo mixes, simply matrixing them into 2.0 wouldn't accurately recreate the theatrical 35mm mix. For that, you'd have to limit them (as they were at the time for the capability of optical sound tracks with Dolby A-type noise reduction).
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THX:

I agree about folding the "baby boom" tracks into one; I forgot about that one. That would definitely work. Agree also about Empire's 6-track master; I now remember there were audio differences between that and the 35mm presentation.

Out of curiosity, does Dolby still use noise-reduction capability for DVD soundtracks? If so, then it would probably be pretty easy to present an original-sounding 2-track print on disc, albeit w/ the limitations mentioned. Still, I'd be fine with it; I'm a huge fan of these films (the originals, that is), and I've always wanted to hear how they "originally" sounded like, especially ANH's mono mix.

Although I've only recently begun posting here, I've been reading posts on this site for months, and I'm impressed with everyone's insight.
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It's an interesting area. The 4-track master would have been mixed in a theater, to include a satisfactory dynamic range. The limiting mentioned would have been added afterward, not as a creative decision, but as a compromise due to the available technology (sound familiar?). So, following your suggestion for the Dolby stereo track would actually be a good example of (getting closer to) presenting the mixers' original vision (used here in the pre-Lucasian sense), even though it was not theatrically presented this way.

Similarly, the 70mm mix was a trial method used to take advantage of new technology. As Dave Schnuelle explained, that technology came to be used differently, so the '93 mix was a somewhat fudged attempt to update the '77 mixes to a contemporary style.

Ultimately you have to ask if you're looking for "theatrical authenticity" or the best representation of the original mix(es) with today's home theater set-ups, which are arguably two different things.
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Check this page out:

http://www.headwize.com/tech/dolby1_tech.htm

"Dolby analog movies and Dolby Surround video and television programs ..... are made using a Dolby MP (Motion Picture) Matrix encoder, which encodes four channels of audio into a standard two-channel format, suitable for recording and transmission in the same manner as regular stereo programs."

"In the theatre, a professional decoder is part of the Dolby Stereo cinema processor used to play 35mm stereo optical prints. The decoder recovers the left, center, and right signals for playback over three front speakers, and extracts the surround signal for distribution over an array of speakers wrapped around the sides and back of the theatre. (These same speakers may also be driven from four discrete tracks on 70mm Dolby Stereo magnetic prints, but in this case no decoder is needed.)"

"One of the original goals of the MP Matrix was to enable Dolby Stereo soundtracks to be successfully played in theatres equipped for mono or two-channel stereo sound. ..... Since the three front channels of the MP Matrix are assembled in virtually the same way as a conventional stereo mix - left in left, center equally in left and right, and right in right - playing a Dolby Stereo mix over two speakers reproduces the entire encoded soundtrack. There is only one thing missing: the surround signal is not reproduced in its proper spatial perspective. When the first home decoder was developed in 1982, its goal was to recover this missing spatial dimension."

Dolby Surround (the 1982 development) was devised to emulate the effect of Dolby Stereo in a home environment by recovering the extra surround sound effects.

I've seen DVDs in stores [case in point: Chaplin's Essanay Comedies Vol. 1-3 released by Image Entertainment] that state 2.0 "Dolby Stereo" soundtracks listed on the back of the case. Would it be possible to simply run the 4-track master through a new unlimited Lt-Rt Dolby Stereo soundtrack master like they did for the laserdiscs (without the "sweetening") and tout it as an actual 2-track Dolby Stereo mix on the back case of the DVD? It doesn't necessarily have to be "limited", although they could still do that if they wanted to. Just a thought.
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Well, the September discs will have Dolby Stereo audio. I'd like it to be matrixed from the 4-track master (despite the lack of total theatrical authenticity) but I don't think that's possible:
Originally posted by: belbucus, quoting Dave Schnuelle
The mixes that are on these discs are all redone directly from the furthest back material that we had...
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THX - Thank you for the detailed reply - sorry it has taken me so long to respond.

I had never seen the article in American Cinematographer. As to my contention regarding the 4-track master, I must defer to you - considering the source. Ioan is a class act and still something of a guru at Dolby, and has never been prone to issuing unsubstantiated information. I still submit that the 70mm and 35mm mixes are distinctly different in many ways including content. There ARE elements in the 6-track that do not exist in the Dolby Stereo version so I assume were not in the original 4-track either. I can only suppose that additional SFX were added during the 70mm dubbing session.

At the risk of contradicting my original post, I also find myself skeptical of one of Mr. Schnuelle’s statements – that the boom channel was simply derived from summing everything and rolling off the top end. Listening to even an “in theater” recording of the 6-track suggests there’s more going on than just added bass across the entire mix. An excerpt from an interview with Mike Minkler, one of the original mixers for Star Wars supports this as well:

(http://mixonline.com/recording/interviews/audio_mike_minkler/index.html),

“…It was a defining moment because of Dolby Stereo. At the same time, it was the birth of baby boom. The 6-track was devised by Steve Katz, who was the Dolby consultant on the show. When we were predubbing reel 1 spaceships, we couldn't get this big thunderous low end that we wanted on the pass-by. We were going to do what we called a “Todd spread” back then, which was to record a left, center and right, and a surround — then fill in channels 2 and 4, the left extra and right extra, with information from these adjacent channels. But Steve said, “What if we used 2 and 4 for boom only, the low-frequency information, and we'll use full-range speakers.” Well, we didn't have them; we had the Altec A4 speakers, and we put low-frequency material in there as much as we could to enhance the spaceships. And every time there was an explosion, there was a sweetener that was cut for those two channels.”

…. the last statement clearly suggesting that they were treating the boom channels selectively, like an LFE. (It should be noted that the 2 boom channels contained the same mono information ((a waste of real estate in some people’s view)). The reason for this decision was that the theaters capable of playing 6 track were all hard wired for Todd-AO – 5 full range screen channels with mono surround. Doubling up the boom channel on channels 2 and 4 allowed for the desired distribution of signal without the need for special wiring, as well as maintaining “backward compatibility”.)

The Baby Boom format (with stereo surround) essentially became the template for 5.1 – five full range channels with one LFE. The 6-track print-masters almost always contained additional LFE information that was not available on the Dolby Stereo mix or the 4-track master, simply because of the technical limitations of the optical release format. Which is why, in the case of pre-5.1 films, the THX Laserdisc Program always extracted their Pro Logic mixes (and later, the 4.1 mixes) from a 6-track source whenever possible. The only reason for sourcing the main channels from a 4-track would be if it were an earlier generation copy - as was apparently the case in Star Wars and Empire. So aside from the generation loss (which is negligible with Dolby A or SR encoded material), I’m still not clear as to why you believe the 4-track by itself represents the optimal source.
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belbucus, thanks for getting back to this, and for bringing useful new information. That Mike Minkler interview certainly does seem to contradict Dave Schnuelle's description. My support for the 4-track master was based on the fact that I don't like the idea of the inauthentic '93 mix or the limiting present in the 35mm print master (despite theatrical authenticity), nor did it seem sensible to have a boom track created in the way Schnuelle describes for the 6-track mix (if he was right, you could more or less recreate this effect at home from the 4-track master anyway). However, from what Minkler says and from your own observations, it looks as if the best option might be 4.1 derived exclusively from the 6-track master. I said above that this would be the most authentic 4.1 mix and it now seems as if it might also be the "best" mix.

Do you have any information regarding the origins of the Laserdisc mixes prior to 1993?
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Originally posted by: Belbucus
I still submit that the 70mm and 35mm mixes are distinctly different in many ways including content. There ARE elements in the 6-track that do not exist in the Dolby Stereo version so I assume were not in the original 4-track either. I can only suppose that additional SFX were added during the 70mm dubbing session.

I've given the 70mm recordings a couple of listens and I did not hear any real differences. Can you elaborate as to what you have found? I'd be very interested to know.

The Starkiller's Guide to the Mono Sound Mix

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I assume you have read everything here: http://www.davisdvd.com/misc/starwars/ep_dir.htm which seems to be accurate.

I imagine you are still interested in details about the ’85. Nothing documented to pass along, sorry. To be honest, I’m not as familiar with the ’85 as the others. When I did a transfer of the original Dolby Stereo from the CAV P&S Laserdiscs, I used bits of it to patch and fill in a few spots. Aside from the modifications in content, it seems very similar the Dolby Stereo - same overall EQ, same restrictions in dynamics and low end. Based on this, and what I now know from the Ioan Allen article (thanks for that!) my guess is that they used the “limited” LT/RT master as the original source. What is interesting is that the stereo image (at least in the few areas I worked with) is wider - particularly the music, which is why I always thought it was remixed from stems. This now seems highly unlikely based on the information in the Ioan Allen article. It’s certainly possible the wider image was achieved through processing, but it does bear further investigation. Any details you know of, please pass them along!

I’m just finishing up the 70mm “in Theater” vs. ‘93 mix comparison mentioned earlier in this thread, which I will try to make available here. Then I’m back to completing the restoration of Moth3r’s mono mix. Perhaps after that I will take a closer listen to the ’85.
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Originally posted by: Starkiller
I've given the 70mm recordings a couple of listens and I did not hear any real differences. Can you elaborate as to what you have found? I'd be very interested to know.
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I haven’t really mapped anything out. It’s mostly bolstering the impact of loud bits in the main channels as well as the boom track. The most illustrative example that comes to mind is where Han takes out Vader’s 1st wingman in the trench. In the 6-track, it is accompanied by a deep explosion that emanates primarily from the left channel and the boom channel. This can be heard clearly in the ’93 mix (and was not one of Burtt’s '93 “additions").
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BTW, my post that preceded the last was in reply to THX. I neglected to make that clear, SORRY!
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Thanks for all your expertise Belbucus--its easy to find people educated in film and video who can dissect the more easily-spotted visual differences but finding audio experts for subtlties like these is truely rare.