Understanding the ADC engine
 

Hello!

I am sending 13 percussion tracks across 13 channels of an analog console to mix on.

I create a Aux bus within PT and also send those 13 channels to the Aux buss. Return the Aux bus to another 2 channels on the console.

The Aux return on the console creates phasing issues, so there is a latency involved.
Attempted with ADC on low and high settings, same issue. It seems to be sending to an aux bus inherently has a small delay.

Kindly advise.

PT HD9.x
192I/o x 3
Mac Pro Core 2 Xenon

Regards,
Sidhu

p.s. I really cant provide detailed info as I am no longer in the studio, but would be returning shortly.

Re: Understanding the ADC engine
 

Not an HD user, so take what I offer with a grain of salt. I thought ADC works for plugins, but to compensate for hardware inserts, you need to manually add the time? At least this is how it works for non-HD users. Check the IO setup page for a tab on delay compensation. It would be something you only need to set once. There may also be function that tells Pro Tools to "ping" the insert path and automatically calculate the time for compensation. You might also check the manual (help files) for info.

Re: Understanding the ADC engine
 

ADC will compensate for the D > A & A >D of a hardware insert . . but not what happens to the signal whilst it's out in analogue world before coming back . . There is no "ping" function.

This isn't the issue in your case as you are just sending to additional outputs,(the pair), via an aux channel in parallel to the individual outputs. .

May I ask why you need to go to a stereo aux & then out ? Are you processing that pair with a plug across the aux ? If so, make sure you can see the ADC on each channel in your mix view. Check that the figure on the aux isn't red .

From memory I think the delay for sending to an aux bus is 10 samples. But that shouldn't be a problem. Try activating "compensate for delays after record pass" in the I/O set up. . Both in & out .
PT manual page 91.
Let me know if that works .

Re: Understanding the ADC engine
 

Yes HD will compensate for outboard gear. You don't have to manually adjust.
You do however have to set the ins and outs on parallel channels for it to work- in other words, output 3-4 needs to comeback into input 3-4 on your interface.
Sometimes this isn't always convenient...I would start here.

Re: Understanding the ADC engine
 

Tx for the time!

It's mostly experimenting. Taking the stereo aux out of PT to the console to compress and eq seperately.

As of now, there are no inserts on any channel within PT, nor on the console. A very straight forward send from the PT mixer to the aux channel, and then returning the aux channel to the analog console causes this phasing issue.

10 samples could cause phasing issues no ?

Ill try ure suggestion, but I thought it was all delay compensated to be sample accurate.

Regards,
Sidhu

Re: Understanding the ADC engine
 

Sometimes I've had phasing issues when running compressed audio with the original source.

Just for example: Take a lead vocal out of PT into an outboard comp, then re-record it back into PT. Then try to blend those two tracks and see how badly it can phase, even if you "time align" them manually.

I haven't read much of this thread and maybe what I'm explaining has nothing to do with what you're experiencing, just skimmed over it. Sorry if this makes no sense lol!!

Re: Understanding the ADC engine
 

There is a good chance that your outboard comp may be doing some phase shifting through its circuits.

Yes. Of course it'll be phasey. The two signals are no longer identical.

Re: Understanding the ADC engine
 

I've noticed melodyne really messes up phasing too.

Re: Understanding the ADC engine
 

Dont forget that it has to be an "insert" as in i/o on insert choices.. not just matching i/o. ff