Digirack inserts...how to deal with sample delay they create?

[glen cannon]

Hey there...question for anyone who might have a clue:

In the protools manual ( I use 4.3.2) it says that if you use inserts or busses, each of these causes a delay of a certain number of samples..
ie. the use of one insert causes a delay of 2 samples ( if I've understood that correctly)

Say, for instance, I've got a quicktime video I'm working to.
If I use an insert like CompressorII on the voice track,does that mean
that, on playback, the voice track is actually 2 samples out from where it seems to be on the screen?

Further, if I then put an insert on my master fader, do I have to move all my audio back 2 samples to correct for this?

Any help would be much appreciated...
I'd kinda feel dumb if I ended up using the inserts heavily and then found out that all my audio in the end was out of sync!
: ) Cheers!

[ppine]

All the outboard gear in a studio has some sort of latency, it has always been there, and generally not been a problem. Now we have the ability to identify the exact delays, and correct them via track slip.

I have on many occasions chained multiple processors in line. I never was concerned about the latency, cause it was not apparent!!
Usually the timing of the performer was mostly in question!!! Next time I'll ask them to try the take again, only 2 samples sooner! http://www.digidesign.com/ubb/images/icons/wink.gif

So bottom line, use the best gear in your studio to decide what/if it needs to be adjusted, your ears!! http://www.digidesign.com/ubb/images/icons/smile.gif

[KSutton]

Certain plug-ins are bigger culprits than others, watch out for in particular Maxim and Waves C1. Try creating a track with no inserts or sends on it. duplicate your audio in question to that track and compare the two . You should be able to hear how far off your processed dialog is, and adjust it accordingly.

[glen cannon]

Hey thanks, ppine and KSutton..
really appreciate your input.

Great idea by the way of putting audio on non-send track and comparing by listening...
: )
I'll do exactly that if I need to...
Cheers!

[blairl]

Command click on the volume level display for the track in question a couple of times and it will tell you exactly how much your audio has been delayed. This is much quicker and easier than duplicating your audio to another track and listening for a difference.

[KSutton]

Does that command click to show sample delay account for all the inserts on that channel? Also do you add that to the selay on the master fader?
Thanks!

[blairl]

The Command click thing does account for all inserts on that channel. In past versions some third party plug-ins were not accounted for but I beleive that all plug-ins are now accounted for in the sample delay display.

You shouldn't need to compesate for any delay on the master fader unless you are using various master faders as sub mixers. The delay compensation is to make sure that everything arrives at the master bus in phase. Once it arrives at the master bus there should be no more compensating necessary.

[Garry]

Glen,

Usually the only instance where a plug in delay might be an issue is one in which you have several recorded microphones for one instrument (a drumkit, for instance) spread out in your session, and you apply different plug ins to the various components of the kit, i.e. compression to the snare drum but not the overhead mikes, a noise gate on the kick drum mike, etc. When recording acoustic instruments with several different mikes at the same time, phase coherence is very important. (are the drum overhead mikes in phase with the snare drum mike, etc.) This is where the delays caused by plug in insertions become an issue, because minute delays such as these can pull things out of phase with each other. Bottom line, take the advice given in the earlier responses to your post, and trust your ears.

Garry Rindfuss