Posted by Fry at pool-151-196-242-83.balt.east.verizon.net on March 17, 2002 at 16:06:14:
In Reply to: There wouldn't be "four mixes"... posted by Vincent on March 17, 2002 at 15:25:39:
Thanks for the correction, Vincent. I should have said compressed/
encoded rather than "mixed" when I referred to the different audio
formats. With that in mind, I assume (again, correct me if I'm wrong)
that remixing for a DVD would involve going back the the
uncompressed 5.1 mix and modifying it, then encoding/compressing
for DVD Dolby Digital. That brings up other questions that you or Phil
could weigh in on. Are there any differences between the encoding
scheme for Dolby Digital cinema and Dolby Digital DVD? I imagine
that the DVD encoding is at a lower bitrate / more compressed. Also,
how many manhours are involved in remixing the audio for DVD,
rather than porting the theatrical mix to DVD along with all the
accompanying disadvantages you mentioned? However much time
it took, I'm sure it was worth the effort.
Thanks again.
: - there would have been two for theatrical- 5.1 (or 6.1, I'm not sure if
J&SBSB mixed in Dolby-EX or not), and a 2.0 Matrix surround mix.
DTS/Dolby Digital/SDDS- there are all DELIVERY FORMATS, *NOT*
mixing formats. Essentially, you're taking the uncompressed 5.1 mix
and then encoding it using one of these delivery formats. Arguments
over the merits of each system have to do with how well the
compressed audion sounds in comparison to the uncompressed
original. The *ONLY* instance where a "special" mix is made
specifically for one of these formats would be if you were mixing for
Dolby-EX, or SDDS using 5-channels up front. But, you're still not
MIXING in those formats, you are mixing uncompressed digital
sound, and then it's compressed and encoded using one of these
systems.
: As for the "special" mix for home- what's usually done in such a
case is, the film is remixed in a smaller room and at a lower level.
When mixing for theatrical, you'll mix in the room the size of a theater,
and when transfering such a mix without modification to DVD, there
can be problems. Phil will know better than I, but from what I
understand, there's a special EQ curve that's applied to theatrical
mixes to compensate for the fact that the film will be playing in a large
theater- I believe it involves ramping up high frequencies that will
otherwise be muted from the sound traveling through the theater
screen (since speakers are behind the screen), plus the fact that the
sound has to fill a large space. When playing a mix optimised for a
theatrical playdate on a much smaller home system with the
speakers much closer to the viewer, the sound can be quite harsh
with high-frequencies that are too hot. So essentially what is done is,
the film is remixed in a smaller room that's closer to a home-
theater's dimensions, with speakers that are closer to the types you'd
use at home. The final *SOUND* will be the same (or as close as
they can get) to what would be heard under an ideal theatrical setting,
but the characteristics of the mix have to be altered somewhat to
compensate for the much different home-viewing environment vs. a
theatrical viewing environment.
: I hope that makes sense. If Phil's around, maybe he can correct any
errors I may have made, but I'm pretty sure this is the jist of it.
: Vincent
:
: : Since you already had four mixes (Dolby SR, Dolby Digital, DTS &
: : SDDS) for the film, I assume (correct me if I'm wrong) that the
cinema
: : Dolby Digital mix was the starting point for the DVD mix. What sort
of
: : modifications were made to accomodate the venue change from
: : cineplex to home theater? Whatever they were, the results are
great,
: : but I'm curious about the changes nonetheless.
: : Thanks.