[BC] DTV Audio Levels

[Cowboy]

On Sunday 14 June 2009 07:01 pm, Ron Youvan wrote:
>  >  Either they have no control 
>  > or they're not paying attention.
>  
>     There are two problems here.
>  Firstly: there is no convent VU meter for a digital stream.  There also no such a thing as a digital 
>  modulation monitor to keep loudness levels consistent between stations.

 That one isn't really a problem.
 One doesn't need any equipment at all to identify a 20 db louder commercial.
 ( even my plastic ears can easily discern the gross level differences )
 Just get it "close enough" and the viewer will tolerate, if not outright be happy.

>  Secondly: there is great reluctance to "un-embed" `monkey with' then "re-embed" network audio, 
>  because: "if you don't monkey with it you can't hurt it" and such equipment isn't in the budget.

 This one is bigger than radio guys can ( at first ) imagine !
 Not only is there reluctance, but that reluctance is entirely justified.
 First, you have to un-embed the audio. Then, you correct the level.
 Now the hard part.
 Now you have to re-embed that corrected audio, AND lip-sync it !
 Doesn't sound all that bad until you consider that you've got a generation loss
 from doing the level adjust, and encode/decode clock rates, etc. etc. AND
 maintaining that lip-sync across various sources, perhaps several during a
 network feed, AND having to do some of it in near real time.
 It's not cheap, or easy, but it *is* digital !

 The "old school" producers still seem to want to control that level, until they
 find out how much trouble it really is.

 At least, that's what I've seen in my limited TV experience.
 Couple more TV projects, hopefully a full studio conversion, and I'll have
 a much better idea. 
 Any takers ?

-- 
Cowboy