Latency Problem with Analog Outboard and Pro Tools 10

Recording Techniques, People Skills, Gear, Recording Spaces, Computers, and DIY

Moderators: drumsound, tomb

Post Reply
Binze
pluggin' in mics
Posts: 39
Joined: Wed Apr 09, 2014 7:09 am
Location: Brooklyn, NY

Latency Problem with Analog Outboard and Pro Tools 10

Post by Binze » Fri Feb 13, 2015 11:23 am

Here's my set up:

Mac Mini running OSX 10.9.5
Apogee Ensemble
Dangerous D-Box
Pro Tools 10
Assorted Outboard Analog Processors

Up until recently I've been sending stems out of my Ensemble into analog outboard gear and then into the D-Box for summing. I'd like to be able to integrate H/W inserts in Pro Tools into my work flow. Ideally, I'll be able to process individual tracks using H/W inserts in Pro Tools while submixes will be processed post DAW (before the summing box).

Unfortunately I've been experiencing some frustrating problems with latency. Here's how I've attempted to set up a parallel drum bus and print the processed track. Bus the unprocessed drums to an Aux and insert the outboard compressor using I/O Insert. Bus the processed drums from the Aux to an Audio Track. Record enable the Audio Track and print. I have delay compensation enabled. The new track that I've printed is actually ahead of the original track and the combination of the two in parallel is a phasey nightmare! Any advice as to what I'm doing wrong here? Why would I be getting this early recording on the processed track? I'm stumped here.

Thanks in advance!

User avatar
digitaldrummer
dead but not forgotten
Posts: 2142
Joined: Wed Nov 23, 2005 9:51 pm
Location: Austin, Texas
Contact:

Post by digitaldrummer » Fri Feb 13, 2015 1:30 pm

I don't think PT10 knows what your hw latency is (since its not Avid hw). So you have to figure out what that latency is and then manually set the offset for the channel(s).

you should be able to record a track or test tone (something with nice transients is probably easiest) and then send it out through the hw and back in to get your round trip latency. You will have to compare it to the original and measure how many samples later it arrived.

or maybe there is an automatic way to do it (I never figured it out in PT9), or maybe Apogee publishes something?

Mike

Binze
pluggin' in mics
Posts: 39
Joined: Wed Apr 09, 2014 7:09 am
Location: Brooklyn, NY

Post by Binze » Fri Feb 13, 2015 1:34 pm

Thanks for the info. I was under the impression (possibly misinformed) that analog hardware should have zero latency. It's digital boxes that you must account for with the manual offset. In any case, I'll send a tone out to the hardware to check this for sure.

John Jeffers
buyin' a studio
Posts: 928
Joined: Sat Jun 07, 2003 1:16 pm
Location: Denver, CO
Contact:

Post by John Jeffers » Sat Feb 14, 2015 10:11 am

Binze wrote:Thanks for the info. I was under the impression (possibly misinformed) that analog hardware should have zero latency. It's digital boxes that you must account for with the manual offset. In any case, I'll send a tone out to the hardware to check this for sure.
The latency comes from the D/A conversion out of Pro Tools, and then the A/D conversion coming back in, not from the analog hardware. That's what you have to figure out and manually compensate for.

Binze
pluggin' in mics
Posts: 39
Joined: Wed Apr 09, 2014 7:09 am
Location: Brooklyn, NY

Post by Binze » Sat Feb 14, 2015 2:48 pm

Ah gotcha. That definitely makes sense. Thanks fellas!

Binze
pluggin' in mics
Posts: 39
Joined: Wed Apr 09, 2014 7:09 am
Location: Brooklyn, NY

Post by Binze » Sun Feb 15, 2015 4:09 pm

I still don't understand why I'd be getting early recording on the processed track. After some research, it's my understanding that enabling Delay Compensation will automatically take the round trip converter latency into account. Also, it's not possible to input a negative value into H/W Insert Delay. Please help! Thanks.

kslight
moves faders with mind
Posts: 2595
Joined: Tue Oct 13, 2009 7:40 pm

Post by kslight » Sun Feb 15, 2015 4:40 pm

The way I understand it, Automatic Delay Compensation within non-HD Pro Tools is a fixed algorithm, so if the amount of latency it is compensating for exceeds the amount of latency you are actually experiencing, it would end up earlier than the unprocessed track.

I'd suggest disabling Automatic Delay Compensation and manually compensating.

User avatar
Nick Sevilla
speech impediment
Posts: 4863
Joined: Mon Mar 03, 2008 1:34 pm
Location: Los Angeles California USA
Contact:

Post by Nick Sevilla » Thu Apr 09, 2015 9:59 pm

Some analog hardware has immense latency.

Like the venerable 660 compressor. And the harder tube compressors and EQs work, they tend to delay things a bit.

Digital hardware devices are also full of delicious delays. At least these are pretty constant.

When I do have to use Pro Tools (Non HD), I tend to keep the ADC ON, and then manually compensate the delay from hardware by moving the effected audio track up by the correct amount of SAMPLES, not milliseconds. After all, the most accurate movement you have within a DAW is one sample.

I do make MARKERS both for the ORIGINAL POSITION of the audio, and the FINAL AFFECTED position. This way, If I end up in a Pro Tools HD system, which I have in my studio, I can then readjust there, if needed. The HD version includes a preference where you can set the hardware delays per hardware output, so you do not have to move the audio anymore, just insert the correct

Cheers
Realizing vibratory excursions from a paper widget.

Post Reply

Who is online

Users browsing this forum: No registered users and 3 guests