Thread: DTV sound synch
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[email protected] stratus46@yahoo.com is offline
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Default DTV sound synch

On Jan 29, 4:29*pm, "Dave Plowman (News)"
wrote:
In article
,
* wrote:

It still does mean something and if you ever thought revenue WASN'T a
part of it, you're just wrong. I get to see 'broadcast quality' video
from the 60's and 70's at work and while it was good in its day, it
doesn't hold a candle to what you have now. I'm one of those 'techs'
and I can tell you we DO give a hoot about how it looks and sounds.


It's very unlikely you are seeing broadcast electronic video from

the 60s
and 70s as good as it was then. It'll have been transferred a few

times as
tape formats go out of use - and the transfer equipment likely

towards the
end of its life. Plus the fact that even a single generation of

quad VTR
caused noticeable degradation, and most of the stuff which has been

kept
will be two or more generations.

--
*If you try to fail and succeed, which have you done? *

* * Dave Plowman * * * * * * * * London SW
* * * * * * * * * To e-mail, change noise into sound.


It IS unlikely but I work in Hollywood and am one of the few who still
get (got?) to work on quads so it happens to be true. I was watching
the original 2" quad tape played back on an Ampex AVR-1 just a few
weeks ago. It was an NBC Danny Thomas special (low band color so there
was some moire) from 1965 with Johnny Carson, Bill Cosby, Tim Conway
and others You're also mistaken about how many generations you can go
down before you have noticeable problems. Network on air tapes were a
minimum of 3 generations down. Mind you, it's necessary to adjust
things properly unlike the newest digital machines that are close to
idiot proof but will tie you in knots with the myriad settings.

You probably never saw a Super High Band Pilot quad tape where the
time base reference was recorded analog along with the analog FM
video. Zero velocity errors as the pilot was the sample clock and any
timing errors on the video were also in the pilot so the error was
nada. That came out in the '70s along with the first 1 inch decks
which had the 'trick' video of slo-mo and still frames which were
previously unavailable to local stations. Quad died fast after that
but not until having a 20+ year run.

I was just repairing Ampex AVR-3s this afternoon.