DMA8 DOLBY E Delay?

[thierryd]

Originally Posted by BRH

Delay is adjustable thru the menu on the processor for each input, no laptop needed.

do you mean you can access the DMA delay settings through a CP or directly on the DMA? Then I really would like to know how to do this. Can you explain or point me to a pdf explanation please?
Thanks!

Greetings,

Thierry

[BRH]

Yes. On Processor CP650 I'm working with DMA8 coming in on input 11 on processor. DCP and HDCAMSR coming in DMA8. On DMA8 itself you can select different inputs, but the adjustment is on input 11 processor(or whatever input DMA8 connected to.)
If running film typically 35mm Dolby SRD is on input 10, SR analog 05 I think, etc. Go into CP650 menu and turn big knob to select input and then select delay and then adjust in ms for that input. Press input button (11 in my case) on processor to save delay setting and exit.. I've done at least 110ms, but I think it does more.
Can do this while film or video is running. This isn't a set up a factory tech would do, like adjusting sound to picture depending on attic reader or basement, or initial setup, but more for user. I need to be in front of the processor to remember actual steps, but it's pretty straight forward.

This helps when videos come in with different sync, especially offline HDCam stuff.

I don't know about initial setup of the DMA8, as I'm just a playback user. (part time mini-major studio.)

Oh, and don't forget to put it back to zero afterward!
It's easy compared to HDCam menu!

[thierryd]

Ok, thanks. You adapt the settings on the CP650, which I was thinking. Believe me, the typical projectionist doesn't touch those settings.
Still to the OP it's a safer bet to advance the Dolby E 1 frame, as it is always easier to delay the audio then to delay the video.

Greetings,

Thierry

[BRH]

Yes, I make most of my living as a projectionist, although we should call ourselves "media managers."
I have never worked in a commercial movie theater.. and it's a sad thing to find most projectionists don't that know what they are doing or won't take the time to set up correctly... or even care about anything. I just do studio type projection. We like the audio to be in sync, but if it's off we will fix it, as the finger will be pointed at us if something is off.
I do a little Protools on the side.. wouldn't be without it.

[nucelar]

Hi!
Something doesn't add up to me about the use of delay on the CP650... I have no experience with the mentioned devices but with dolby E.

AFAIK the DMA8 is just an audio interface, it passes audio in different formats to the CP650. As any Dolby E decoder, it will introduce 1 frame delay to the decoded output, no more, no less. (41.67ms @ 24fps)
if the Dolby E stream is "sync on tape", the video must read 1f later (vtr handles this)
if the Dolby E stream is "sync on playback", there's no need to delay.
So why would you want to delay the audio signal further with the CP?

Cheers

PS: I would definitely contact dolby to get an authoritative answer

[garret]

Just to update anyone who cares. I spoke with James at Dolby and he said to go the usual Broadcast route and have it in sync on tape. With the projector introducing delay in the picture (3-4 frames) the DMA8 can have different delays on each input so if calibrated correctly all should be well. Fingers crossed

Thanks

Garret