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  1. First off, I am really new to audio editing (I've been playing around with Kristal Audio Engine, Audacity, Wavepad, BeLight, etc.) and was wondering if these programs or any other free ones can encode (not convert to) 2.0 surround audio. I've read that you can mux six mono waves into 5.1 surround and flag it for pro-logic downmixing (under the "Output" option in Azid settings) with BeLight (I have no idea how to use any of these programs without a GUI) and was wondering if the same can be done with the "stereo" option on the same program (or any other encoders)?

    I'm really not anywhere close to actually doing any of the work yet (I'm still reading up on mixing 2.0 surround through print-outs from forums and Dolby technical documents) so I'm just looking for general answers (or links).

    Thanks in advance for any help.
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    2.0 is stereo. What do you mean by 2.0 surround?
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  3. Member Cornucopia's Avatar
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    He's talking about Dolby Surround (aka PL, PLII)-encoded 2.0.

    You need a Dolby Surround matrix encoder. There are some recent threads here and over at Doom9 on this subject (incl. some of my posts).
    -or-
    You can roll your own with out a proper encoder by creating phase-adjusted submixes. See further on in some of those same posts.

    Note: it's not that easy to do. In fact, I find it much easier just to do a true 5.1 mix.

    Scott
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  4. "You can roll your own with out a proper encoder by creating phase-adjusted submixes. See further on in some of those same posts. "

    So, a proper encoder would automatically phase-adjust the surround but you would have to do it
    manually during mixing before muxing and encoding the submixes to AC3?
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  5. Member Cornucopia's Avatar
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    Yes
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    Hi there,
    Dolby 2.0 interests me, as it's something I've been curious about...
    If 5.1 surround stands for FL, C, FR, SL, SR and ".1" for the LFE, then what does 2.0 stand for? Using the same logic as 5.1, wouldn't you think it simply means a left channel, a right channel, with ".0" representing nothing?! ... ...
    Please enlighten me, 'cause I'm obviously clueless here, heh
    - Justin
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  7. Member yoda313's Avatar
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    Yep 2.0 is just that. Left and Right. No low frequency. Though it CAN include surround information using Dolby Pro Logic. Its just not digital surround sound.
    Donatello - The Shredder? Michelangelo - Maybe all that hardware is for making coleslaw?
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  8. So once you manually phase-adjusted the surround information, would you still have to find a way to flag the track for DPL?

    I find it much easier just to do a true 5.1 mix.
    I'm starting to see that but as a newbie just learning the terms and concepts, I find the matrix encoding more fascinating than the discrete (?) encoding.

    Somewhat related: I have a DVD of a film with a DD 5.0 track and an optional M&E track in 2.0 surround, would that mean that the M&E track is a mix-down of the discrete left, right, left surround, and right surround tracks (I think the 2.0 mixes on other releases of the film are DD stereo not surround and I guess the 5.1 mixes extract low frequency info from the other tracks or add effects to the track)?
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  9. Member Cornucopia's Avatar
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    In the context of Audio (and probably Video for that matter), the terms

    Discreet

    and

    Matrixed

    have particular meanings:

    Discreet = Each item (stream/channel) in bunch is independently self-contained and isolated from intermixing with other streams. Input always equals output

    Matrixed = Each item in a bunch is intermixed with it's partner item(s) in a particular formula that makes use of Matrix Algebra to mix and to unmix (using specific coefficients) the items and finally return them to their (near) original state. It is in a way a type of compression. Unfortunately, it's like a type of lossy compression--Input is never quite equal to output. There is always some intermixing that doesn't get undone.

    This used to refer in the analog world to the medium and the contents. Now, with digital it can mean either medium or contents, or both.

    Example: 4 channel audio in AC3 file format can be 4.0 which is discreet, or be 2.0 and be matrixed (from Quad/DolbySurround/Ambisonics/etc). Since AC3(mp2, etc) is lossy anyway, adding matrixing to the equation creates a file which will be decoded with even LESS fidelity. That's another reason why discreet is better.

    ecc > Yes, you flag the 2.0 track as DolbySurroundEncoded (it should be there as an option in you AC3 encoder).
    Remember the ".1" in 5.1 refers to "LOW FREQUENCY EFFECTS", not just LOW FREQUENCIES. All the regular 5 channels have full frequency range.
    People get this regularly mixed up with the playback adjustment of satellite/subwoofer crossovers and bass management issues. Related, but Not the same thing.

    yoda313 > like I just stated, AC3 2.0 has low frequency capability. It also may or may not be Dolby Surround (matrix) encoded. This is still "Digital Surround" though, as it's a digital file. It's just not discreet surround (unless you count 2.0 Binaural ! 8) ).

    Scott
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    Wow,
    No wonder so many people go to particular colleges meant just for this stuff. It can get rather "deep".
    Luckily, this forum and all you kind people tend to provide a wealth of knowledge that you don't even need to get schooling for.
    That said, I still plan on trying to get into the sound engineering field, which will require me to attend some school located God knows where *shrug*
    The reason I was interested in Dolby 2.0 is because I noticed that Fright Night has either mono or 2.0 to choose from and Crash has Dolby 5.1 or 2.0 to choose from. I simply don't understand why you'd want to choose 2.0 if you have 5.1 as an option. Furthermore, what is the point of choosing 2.0 over mono when you'll hardly heard much of a difference?
    I'm lost again
    - Justin
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  11. Member Cornucopia's Avatar
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    Well then I'll just put a plug in for my alma mater: Hook 'em Horns! (U. Texas @ Austin). Got my Radio-TV-Film degree there. It's a great school for that, plus the city's a place you won't want to leave. I still learned more than 1/2 my stuff afterwards, but you can hardly get a better foundation.

    re: multiple mixes on a DVD,
    I think the lower # may be the "original" track (for those purists) and the higher # might be a remixed track. Or they realize that their particular soundtrack doesn't automatically downmix to 2.0DPL very well (hopefully the stuff I said recently would help you see that possibility). Has alot to do with the aforementioned "phasing". Plus, there's the very real fact that when automatically downmixing from 5.1 to 2.0, the ".1" channel is just completely dropped/ignored. So if you wanted good EXPLOSIONS and such to be heard by all those without HomeTheatreSurround systems, you'd want an alternative.

    I can hear a big difference between 2.0 (reg stereo OR surround) vs. 1.0.

    Scott
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    Well,
    I live in Buffalo, so I'm not sure Austin is too feasible ... I think I'd need to perhaps try NYC *shrug*
    The thread regarding phasing is something I need to read again, very slowly, heh. It didn't quite sink in entirely.
    Here's a question for you that I've asked before and haven't yet received a definitive answer to:
    When the pros create a 5.1 mix, do they use the source tapes or do the take the mono soundtrack that is already mixed and use various techniques to create the surround sound? There are some cases where you'd think the source tapes would be too worn out to use, yet the results are impressive, ie. The Omen, The Exorcist, etc. If they DON'T use the source tapes, I don't understand what hardware/software and techniques they use to create such an impressive mix. If they DO use the source tapes, I'm impressed by how well they've held up over the years. Then there's the possibility that some are from source tapes and others are the premixed... I really have no idea
    - Justin
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  13. Member Cornucopia's Avatar
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    You prob. already know that NYU or Columbia is good for this sort of stuff. Hope you can make one of those (but $$$$??)...

    The definitive answer is that there is no definitive answer.

    Masters have been different over the years. If given the choice (tech opportunity) and it's economically feasible, Remixers would almost always go for the original stems (separate FX / Music / Dialogue submixes) or raw multitrack to mix from.

    But you got to remember it wasn't until "Dolby Stereo" (mid 70's) that the average (maybe above average) movie was anything more than optical or mag mono. Digital didn't take hold in film until mid/late '80s.
    Before that, multitrack mixing didn't start until late 60's-early '70's. Before that, you might do a 2- or 3-machine sound-on-sound mixdown to a later generation master. Most of that stuff would be done professionally on Reel-to-Reel using 7 1/2 or 15 or 30 ips speeds and 1/4", 1/2" or 1" tape. Anything before mid-50's was before magnetic recording, so you only have optical soundtrack (almost always mono) or maybe phonograph sync master.

    Still, these analog masters can be fairly high quality. It's not like they were using cassettes as their masters. The specs for much of the material might be as high as ~80Hz-14kHz, with ~40-60dB SNR.

    When going from mono/stereo to surround, they could do a piece-by-piece reconstruction ($$$) or fake it with surround synthesis ($ but crap) or a mix in between, but it makes sense do different things to the Music or FX stem vs. the Dialog. So it's not too difficult to come up with a passable surround, if the original audio staff did a good job of archiving.

    Scott
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    Hi again,
    Thanks for the reply. Yeah, I did check out info. on NYU in the past and you're right, disgusting amounts of dough required :/
    "It's not like they were using cassettes as their masters." ... Heh, I know. I just assumed that over time even the highest quality source(s) would lose a lot of quality.
    So, the good news for those that enjoy great 5.1 remasters is that many companies keep "clean" archives, right? This is somewhat bad news for someone like myself, that only has software and a soundtrack that has already been mixed. All I can do is try my hardest and hope that an attempt at creating even 5 minutes of a 5.1 mix doesn't have me pulling my hair out
    Am I right in my assumption that many films you'd *think* would be remastered to 5.1 and weren't probably didn't have the greatest quality sources to rely on? For instance, I would've thought without a doubt that the original When a Stranger Calls would have a 5.1 mix, but no. Actually, even just the mono soundtrack alone is rather poor, so I'm guessing I might be right on this one. *shrug* ... it just pains me when I notice things even as simple as footsteps and you can barely hear them. Even Carol Kane's memorable phone conversation is far more quiet than I care for. Though, I can understand why... I once tinkered with that piece of the soundtrack and greatly boosted it. I discovered that, unlike other soundtracks I've experimented with, this resulted in an enormous amount of hiss... again, a possible reason why it wasn't remastered to 5.1. Those in charge might be a prime example of those that don't keep "clean" archives.
    "...they could do a piece-by-piece reconstruction..."
    Can you elaborate on what this means? Is piece-by-piece a method where they try to work on the soundtrack in various "chunks"/intervals? If so, it must be extremely tedious, not to mention time consuming.
    Thanks again,
    Justin
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    Yes. Having done "piece-by-piece" reconstruction/restoration, it IS a tremendously tedious and laborious process. But alot can be done.

    'Coupla years ago, I took on a personal project to totally restore (or more likely "enhance") an old, old soundtrack. Got the idea in college when I saw a showing of Marx Bros. "Duck Soup", which was a VERY early talky and suffers greatly in the noise/quality area.
    Since then, I came up with a number of "processes" that would help with restoration, some predating computer DSP enhancement/NR stuff. I used as my sample the '40's Bogart version of "The Big Sleep". Some of the stuff is still proprietary, so I can't go into detail, but the basic flow is as follows:
    • 1. Best archival master research/detecting
      2. Physical analog media restoration
      3. Highest quality transfer/digitization
      4. Track duplication
      5. Catalogging of all elements (Dialog-words, sounds; SFX; Music)
      6. Element isolation (by time, frequency or amplitude domain) as far as possible.
      7. "Cleaning" digitally with Broadband NR, declick, de-hiss, EQ, etc.
      8. Heavier processing using cleaned "guide tracks"
      9. Reconstruction/Resynthesis/Replacement
      10. Remixing

      ...All the while doing multiple comparisons/blending with the original @#3.

    It's cool stuff if you want to dig in.

    And yes, I agree about your assessment/guess of the relationship between master quality & remasting choices.

    Scott
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    Hm,
    What's interesting, or perhaps disturbing (by some people's standards), is that what you described actually sounds like something I'd be interested in, despite the work involved.
    My belief is that so long as what you're doing WILL produce the results you're hoping to achieve, then why not work on it? This is especially true if you have the money and the time. I have lots of the latter, but none of the former
    The dedication and persistance is there, so I'd be more than willing to have at it.
    However, what you described sounds extremely pricey. Therefore, this would be more of a long-term goal :/
    One of the many glaring questions off the top of my head is, how do you obtain the source tracks? This alone must be quite a task. I'm thinking you'd have to do something along the lines of:
    -
    1. Locate the "root" of the source tracks, perhaps by contacting the distributor. Even just this step would probably be tricky, as they'd most likely try to give you the "runaround". After all, they don't want to give such valuable information to just anybody.
    2. Provide valid information on what exactly you're trying to do/why you want the tracks.
    3. Receive permission to use the tracks, but only under "who knows what" circumstances.
    4. Sign release documents.
    5. Pay, I'm afraid to even ponder how much, to finally receive the tracks.
    -
    I "know" someone that works for a theater that told me certain things I was unaware of. For instance, I didn't realize that you have to know well in advance just how much you can get done with those tracks within a given amount of time. I've been told that a distributor will only allow a pretty d*mn short length of time for you to keep even the smallest amount of material. I recall being told that you only have a week, including the time it takes to ship back and forth.
    Arg... it's very irritating when you'd like to try to work on a project, but have no idea how to even start. I appreciate your replies though. It's encouraging to know that people are willing to lend a helping hand.
    Thanks much,
    Justin
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    BTW,
    I'd greatly appreciate it if you could test something out for me. Here's a link to a very short ac3 clip:
    -
    http://www.filegone.com/ynij
    -
    I tried to do something unique with the surrounds, but I have no clue how it turned out. I have a feeling it might be a bit messy, so please let me know what it sounds like.
    Thanks,
    Justin
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