At 01:26 AM 7/6/2006, seva wrote:
>one big caveat: most DVD players have built-in dynamic compression.
>most SONY players have it default to "normal" which is not normal at
>all; after a near debacle after a client reviewed a Reference copy,
>it was found (after i insisted there was something Fishy About the
>Player) that the "normal" setting was hardly that; instead they
>needed to select "wide" range, which was actually unaltered playback
>dynamics... although it was never stated so in the manual at all.
>weirdly, this only affected the discrete analog outputs and not the
>digital out (makes no sense, eh).
I think this is part of the Dolby Digital standard, actually. I'm not
involved with this day-to-day, but before I went into audio tape
restoration full time in 2004, I was designing high-end broadcast
facilities and had some interaction with the Dolby folks then and a
bit since. I'm in the midst of several crunches and can't look it up
right now, but the Dolby dynamics bit defaults, I think, to some
overall compression. There are three different named variables (IIRC)
correctly that affect this: Dialnorm, Downmix, Dynamics or something like that.
Dolby Digital is a complex system and it's incorporated in all DVDs
and over-the-air ATSC broadcasting. I spent a bit of time last
fall/winter with Neil Muncie discussing this and he's spent far more
time analyzing and discussing with cable head-end operators how to
set Dialnorm. I really suggest that anyone involved with this study
(and it will take a day or more) the technical "white papers" "mixing
guides" or whatever they're called on the Dolby site ( www.dolby.com )
Just as we understood how vinyl modified the signal and compensated
for it, we must understand how Dolby Digital modifies the signal.
This time, we have the option of setting the desired bits as part of
the mastering or authoring process. We have control over much of
this, if not all.
Richard L. Hess email: [log in to unmask]
Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.