Delay through De-embedder/Embedder

Hello,

I want to use a SDI-Audio - Audio-SDI converter pair to Bring out audio to an external processor and return back into the SDI.

What kind of delay will the de-embedder and embedder add to the situation?

Jon

[Sarah Jones]

The delay is going to minimal. For each device, you're looking at about a couple lines of delay, so if you have the SDI to Audio followed by the Audio to SDI, you're looking at maybe four or so lines of delay total. You'll also want to factor in any delay that your external processor is bringing to the table. But from the Mini Converters, like I said, you're looking at about four lines.

To expand on Sarah's answer, it's worth pointing out that this same amount of delay is imposed on the video as well... so if you are concerned with audio remaining in sync with the video, it's absolutely a non-issue since the delay is a very small fraction of one video frame.

On the other hand, if you're using the embedded audio to feed live audio where the delay is audible -- for instance, if you're trying to use the embedded channels to create a digital snake -- there might possibly be an issue. Four video lines in a 525-line system (worst case) would yield about 250 microseconds of delay; at 1080i, the delay drops to about 125 microseconds. And as she points out, this is exclusive of any other processing delay created by the rest of your gear.

Regards,

-- Jeff