Making a DCP from a 2-channel stereo Blu-Ray

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  • Marcel Birgelen
    Film God
    • Jan 2020
    • 3619
    • Maastricht, NL

    #16
    Originally posted by Gordon McLeod
    We make our DCPs with Davinci resolve studio version and the DTS nerual plug in that offer a prologic upmix to the DCP
    The DTS Neural plugin does more than just a Pro-Logic upmix and will give you, out of the box, a far better experience than just Pro-Logic, it's also better dan Neo:6, although it apparently uses some of the same algorithms. It's not really cheap though, at least not if you're not doing this regularly. The same for the DaVinci Studio version.

    I've used the DTS Neural Plugin quite a few times, there are better alternatives nowadays, but it's a good tool to create a 5.1 mix from plain stereo.

    Comment

    • Mike Blakesley
      Film God
      • Jan 2020
      • 2021
      • Forsyth MT

      #17
      What is the name of the movie are you screening privately?
      I don't want to publish the title here because some studios are very irritable about "sharing" the screen with another movie and I don't want to get in trouble with the studio that owns the movie we'll be showing for the regular show that night. (I'm not sure what we'll be showing on that day yet.) This private showing will be in the afternoon.

      What's weird is, it's a 1990 movie, which was well into the 5.1 era, but were there still mono movies being made at that time? Maybe this movie had a 5.1 mix but that's been lost to the ages?

      I had a BR of "Edward Scissorhands" that I wanted to convert just for my own use, but that Blu-Ray also has a L/R mix, and that movie is about the same vintage as the title in question.

      For what it's worth, our auditorium is about 32 feet wide and our left and right speakers are about 25' apart, so maybe the "phantom center" thing might work?

      We have an Odyssey2 processor from Trinnov and a typical 5.1 sound system.

      I'm tempted to just make 2 DCPs, one with the sound all piped to the center and another with the L/R mix left alone and just do a comparison.
      Last edited by Mike Blakesley; 05-18-2026, 02:22 PM.

      Comment

      • Ryan Gallagher
        Film God
        • Nov 2022
        • 2855
        • Austin, Texas, USA

        #18
        Originally posted by Mike Blakesley

        I'm tempted to just make 2 DCPs, one with the sound all piped to the center and another with the L/R mix left alone and just do a comparison.
        Well I would ignore the Mono, unless you think the disc is a two track mono. Most commonly with DOM from stereo You'd be upmixing to 3 channels using their LCR matrix option. DOM can't get you all the way to 5.1 that I'm aware of, although they just added some options to that area recently and my memory is fuzzy.

        Note your 2nd DCP creation should go faster if you do it as a VF, assuming you use DOM, it won't have to re-encode the video frames.


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        • Marcel Birgelen
          Film God
          • Jan 2020
          • 3619
          • Maastricht, NL

          #19
          Looks like everybody has an opinion... fine, at least Mike has some options to choose from. :P
          ​
          Did Woody Allen ever release something not mixed in mono? IMDb is sketchy on the details, even something released in "Atmos" can eventually just be a mono mix...
          Theatrical movies mixed in just stereo, I doubt there were any from the big Hollywood studios in the 1990s, I know that some indy productions mixed their stuff in just stereo. There were plenty of direct-to-TV productions that were mixed in just stereo too. But not all movies got the major Blu-Ray treatment. Somewhere in the late 1990s they began to scan movies in 2K and many DVD and Blu-Rays used the same master. But even DVD did already support a bunch of digital surround formats. Why a 4-channel or even 5.1 channel mix would get lost is difficult to fathom, but Universal had this big fire back in 2008 and rumors are they lost more than they claimed they lost back then...

          Dumping it all into the center channel is something I would NEVER do. Yeah, there might be exceptions, but I dare say: bad stereo is better dan convoluted mono.
          But... I guess you meant the Ovation 2 from Trinnov?

          Instead of upmixing via the LCR matrix option, I'd check the manual of your "Odyssey 2", because marketing material claims it can do upmixing and the whole purpose of the thing is being an audio processor.

          Otherwise, upload the MKV somewhere and I'll make you a "proper" 5.1 upmix.

          Comment

          • James Gardiner
            Expert Film Handler
            • Nov 2021
            • 500
            • Melbourne, Australia

            #20
            I have used Waves UM225 or UM226 plugins​. https://wavesjapan.jp/plugins/um225-um226/ , mainly for ads. While they offer a lot of options and configurability, the results can be inconsistent. Sometimes it takes a second for the plugin to calculate the best way to separate the frequencies, resulting in audible shifting. Ouch. After doing quite a bit of this work, my main conclusion is that upmixing is an imperfect process and a major compromise. For feature content, I often feel that if it was mixed in 2-channel, it should stay in 2-channel. I also disagree with the argument that Dolby Pro Logic—an outdated algorithm built on slow ASIC technology—is superior to modern CPU-rendered implementations. We have to remember that Pro Logic originally operated on optical sound, which was incredibly poor quality. In my opinion, it simply involves too many technical compromises.
            But at the end of the day, if it sounds better, it sounds better. Specific workflows will always have their place depending on the target market and use case.
            ​

            Comment

            • Scotty Wright
              Pro Film Handler
              • Jan 2020
              • 138
              • Seattle, Washington

              #21
              Originally posted by Mike Blakesley
              I had a BR of "Edward Scissorhands" that I wanted to convert just for my own use, but that Blu-Ray also has a L/R mix, and that movie is about the same vintage as the title in question.
              Not to ruin your dcp experimentation, but there’s newer Blu-ray’s of Edward Scissorhands with DTS 4.0 or Atmos mixes. The home Atmos mix has a base Dolby TrueHD 7.1 mix.

              Comment

              • Marco Giustini
                Film God
                • Jan 2020
                • 1169
                • Reading, UK

                #22
                Originally posted by Marcel Birgelen
                Did Woody Allen ever release something not mixed in mono?
                Yes

                At least one of his late movies had some reverberation in L and R, to make the Centre channel a bit less dull in a modern sound-treated room. No more than reverbs though

                Comment

                • Marcel Birgelen
                  Film God
                  • Jan 2020
                  • 3619
                  • Maastricht, NL

                  #23
                  That explains the Atmos release, gotta have Atmos for those reverbs.

                  I think I haven't seen a Woody Allen movie in over a decade. The guy seems to be somewhat controversial nowadays, but he's 90 now and apparently still cranking out movies.

                  Originally posted by James Gardiner
                  I have used Waves UM225 or UM226 plugins​. https://wavesjapan.jp/plugins/um225-um226/ , mainly for ads. While they offer a lot of options and configurability, the results can be inconsistent. Sometimes it takes a second for the plugin to calculate the best way to separate the frequencies, resulting in audible shifting. Ouch.
                  Our experiences with the Waves UM225 and UM226 plugins are better than those with DTS Neural. Best results hands down though, and also most flexible to use have been the Penteo Pro+ plugins from PerfectSurround. They aren't cheap though, especially the "Atmos upmixer", but for a professional solution, I guess, more than reasonable.

                  Still, even "PerfectSurround" isn't perfect and sometimes needs some cleaning up work.

                  Originally posted by James Gardiner
                  After doing quite a bit of this work, my main conclusion is that upmixing is an imperfect process and a major compromise. For feature content, I often feel that if it was mixed in 2-channel, it should stay in 2-channel. I also disagree with the argument that Dolby Pro Logic—an outdated algorithm built on slow ASIC technology—is superior to modern CPU-rendered implementations. We have to remember that Pro Logic originally operated on optical sound, which was incredibly poor quality. In my opinion, it simply involves too many technical compromises.
                  But at the end of the day, if it sounds better, it sounds better. Specific workflows will always have their place depending on the target market and use case.
                  Usually, you use ASICs when general purpose CPUs and even FPGAs aren't cutting it anymore. . Also, I doubt that the earliest implementations of Dolby Stereo and Pro Logic did use any discrete technology at all, because "Pro Logic" isn't anything other than just some simple phase-shift magic, which can be implemented with some well-tuned analog delay lines. The center channel is even more simple, it's essentialy a somewhat boosted sum of L+R:

                  NFjrxGq.png
                  Last edited by Marcel Birgelen; 05-18-2026, 05:41 PM.

                  Comment

                  • Mike Blakesley
                    Film God
                    • Jan 2020
                    • 2021
                    • Forsyth MT

                    #24
                    I guess you meant the Ovation 2 from Trinnov?
                    Indeed I did mean that. Hey at least give me credit for spelling Trinnov correctly!

                    Comment

                    • Marcel Birgelen
                      Film God
                      • Jan 2020
                      • 3619
                      • Maastricht, NL

                      #25
                      One "Like Credit" awarded for spelling Trinnov right.

                      What you probably didn't know (and me neither, because I had to Google it...). The company is called Trinnov not because someone with a slavic sounding surname started an audio lab, but because it's a contraction of "Tri" as in three (for 3D) and Innovation...

                      Do I get a random-useless-information-dump credit for that?

                      Comment

                      • Leo Enticknap
                        Film God
                        • Jan 2020
                        • 3572
                        • Loma Linda, CA

                        #26
                        And could I get one for revealing the nerdy factoids that Adidas is a contraction of Adolf Dassler, and the 2CV in Citroën 2CV stands for "deux chevaux" - two horses, because its engine has two horsepower? Returning somewhat to topic, QSC was originally QST (Quilter Sound Things), but Things was changed to Company in the 1960s, as it was growing beyond the scale of a guy in a garage enterprise.

                        Comment

                        • Marcel Birgelen
                          Film God
                          • Jan 2020
                          • 3619
                          • Maastricht, NL

                          #27
                          Nerd Credit Given...

                          Mine was halfway on-topic though...

                          In regards to Adidas though, HARIBO comes to mind, which is a contraption of: Hans Riegel, Bonn​. Just like almost any German company that was active during Wold War II, it's said to somehow have profiteered from that war. Hans Riegel wasn't a Adolf Dassler or Hugo Boss though... But hey, just look at how current big tech execs all line up to creep into the buttholes of the asses currently in charge. Enough with the politics already... Let's talk about Stereo!

                          Comment

                          • Leo Enticknap
                            Film God
                            • Jan 2020
                            • 3572
                            • Loma Linda, CA

                            #28
                            OK. In a non post-house/premiere/high profile screening scenario, whether to upmix or not, and if so how, is likely best determined by a subjective evaluation. In my projectionist days I found that in 99% of cases, ProLogic upmixing generally worked well, and avoided the "phantom center" problem that can make dialogue hard to understand (the second most frequent cause of customer complaints about audio, after too loud). I encountered this problem often at the Egyptian, usually when film fests with low budget or student entries that had a 2.0 mix on them were in town. Our solution was to run the AES3 audio from the DCP server through a DMA8+ on its way to the audio processor. This gave us the ability to pass it straight through or apply ProLogic upmixing at the touch of a button. It annoys me that the CP950 will not upmix from the AES3 input, but will from the others. A positive point about using a Q-Sys core as the audio processor is that it can pseudo-ProLogic upmix from anything, and I include the ability to upmix 2.0 DCP audio in my designs. I also encourage projectionists to listen first before doing so for an actual show, though.

                            Comment

                            • Christos Gartaganis
                              Film Handler
                              • Sep 2021
                              • 53
                              • Athens Greece

                              #29
                              I have used the Penteo Pro+ plugin on several projects so far, and I agree with Marcel that if properly tweaked the upmixed audio is very close to the original 4.0 or 5.1 mix if the feature's multichannel soundtrack has been lost and the only available source to work with is the Lt/Rt print master (most likely encoded with Dolby SR noise reduction)

                              Comment

                              • Harold Hallikainen
                                Film God
                                • Jan 2020
                                • 1073
                                • Tucson AZ

                                #30
                                Speaking of upmixes, did anyone try the Lexicon QLI-32? USL was involved in the design and manufacture of it. We installed one with 32 speakers in a local theater. I remember seeing Deepwater Horizon with the QLI-32. Sounded pretty nice!

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