Analog inserts/sends and latency?

[tlester]

Hi all -

I know that of you option click on volume you can get how many samples of latency has been generated by plugins. If I insert an analog device on the channel, will it add it's latency to that calculation as well?

Also... once you do compansate manually by nudging the audio earlier in time, does the read out adjust. I.e. if the latency was 13samples, and I nudge back 13samples, will the reading now say "0"?

Thanks,
Thomas

[davip]

Time adjuster comes with Protools. It doesn't shift the track back to compensate for plugins, so it won't made the delay show as zero samples. You use it on other tracks to match the delay of all your tracks.

The delay for aux sends is in the manual. Come to think of it, I think it's wrong in my edition of the manual. I had to determine it by bouncing a file, importing it and finding the delay for myself. I wish I could remember it now!

[Kev]

Yep davip is right, my bad.
I didn't explain that at all well. You can get all tracks in PT to show the same delay. It gets more complicated when you use subgroups and external mixing things.

I think the aux out delay on Mix/888 is 18 samples. BUT as with all things it is best to set up a test and prove stuff for yourself.

[Kev]

Originally posted by tlester:
Hi all -
If I insert an analog device on the channel, will it add it's latency to that calculation as well?

..... if the latency was 13samples, and I nudge back 13samples, will the reading now say "0"?

<font size="2" face="Verdana, Arial">I don't think so. [img]images/icons/rolleyes.gif[/img]
How is PT going to know about an external device and even if it did ... it could be a delay device.

No ... BUT if you use Timeadjuster in the last plug insert position, it will.

[tlester]

Is timeadjuster a built in digi plug? Or is it third party? If so, who makes it?

-t

[nickair]

Just a question because we're talking about latency.
You were talking about 18 samples of delay for the AUXs on a 888. If we're working in 48k, 18 samples represent about 0.000375 seconds. Do you think it really represents something, that finally becoms audible (regarding the phase, or whatever)? And even if we add 10 or 20 times the problem, it will be about a few miliseconds, which may cause some audible effects on percussive material... What do you think?

[Nimrod]

The delay sample value will only be broadcast for digi plugins. it will not tell you the value of inserts etc. The way to find out the delay value is to do phase nulling experiments with each plugin and insert. I found that the delay value for an analog insert on HD192 is 93 samples rather than 103 as stated in the manual. these figures are a little misleading. To find the value of a plugin or insert do the following. Creat a new session import a short piece of audio such as a snare drum hit. Assign it to a mono output. Duplicate it. Put a plugin on one of the duplicate tracks. For example Oxford EQ (put in bypass mode, the sample delay is the same). Now play them together, there will be audible phasing. Put TA on the other track with 4 sample delay and hit phase invert switch, the sound nulls completely because the sample delay of the Sony is 4 samples.

Hope this helps

James Cullen

Seabrite studios

[Krusty]

93 samples?

ok, everyone keep in mind.... each interface has differnet latencies for analog and digital inserts. they are listed in the manual.

Alos, remember that this latency measurement must be dolubled. Example: 93 samples for D-A and 93 samples for A-D..... plus so many people seem to forget that outboard processors have some delay as well. they always have. some have more than others and it won't be listed anywhere, so you'll need to experiement.
Massive cable lengths and patch bays can make a slight difference too.

[Matt Zeiner]

people seem to forget that outboard processors have some delay as well.

<font size="2" face="Verdana, Arial">yes - important to note this only applies to digital processors - obvious, I know, but not mentioned. Analog comps/eqs have no delay.

[Matt Zeiner]

Massive cable lengths and patch bays can make a slight difference too.

<font size="2" face="Verdana, Arial">Not really true. In theory, yes, but electrical signals travel through wire at approximately the speed of LIGHT......