Avid Pro Audio Community

Avid Pro Audio Community

How to Join & Post  •  Community Terms of Use  •  Help Us Help You

Knowledge Base Search  •  Community Search  •  Learn & Support


Avid Home Page

Go Back   Avid Pro Audio Community > Pro Tools Hardware > Pro Tools | MTRX & MTRX Studio

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 11-29-2023, 04:06 AM
mahler007 mahler007 is offline
Member
 
Join Date: Jun 2004
Posts: 330
Default Massive latency b/t MTRX Studio & Aurora(n) Dante

Hi,
Just got a 24-channel Aurora(n) with the Dante card. Going from Primary port of MTRX Studio to my Mac Studio (Ventura) for DADman, and have plugged the Aurora into the secondary port of the MTRX Studio. Am using CAT5 cables for both. There are no other i/o devices in the setup.

I believe have everything configured correctly with Dante Controller and DVS. The Aurora is sending and receiving signal to/from Pro Tools, no problem. I don't see any weird errors in the Dante Controller software.

I am using the Aurora primarily for hardware inserts, and am getting hundreds of ms of latency. In a total head scratcher, the channel that has the HW insert via the Aurora is showing back up in Pro Tools BEFORE the other session audio.

Any ideas on what might be going on here? Some questions come to mind:

1) Should I use an external switch rather than the secondary port of the MTRX Studio for the Aurora?

2) Could poor cables be the culprit?

3) Is Dante a poor choice for using with hardware inserts? I am aware of Dante's internal latency, and don't really care, so long as I can get everything properly sync'd (I have a small console for 0 latency monitoring/recording).

I've been suing an old, 16-channel Aurora via LT-HD for about 15 years, and have *never* had any problems with latency, so this is a bummer. Wondering if I should switch back to LT-HD2 for the new Aurora(n).

Thanks for any tips!
Reply With Quote
  #2  
Old 11-29-2023, 06:07 AM
Darryl Ramm Darryl Ramm is online now
Member
 
Join Date: Nov 2010
Location: USA
Posts: 19,657
Default Re: Massive latency b/t MTRX Studio & Aurora(n) Dante

Quote:
Originally Posted by mahler007 View Post
Hi,
Just got a 24-channel Aurora(n) with the Dante card. Going from Primary port of MTRX Studio to my Mac Studio (Ventura) for DADman, and have plugged the Aurora into the secondary port of the MTRX Studio. Am using CAT5 cables for both. There are no other i/o devices in the setup.

I believe have everything configured correctly with Dante Controller and DVS. The Aurora is sending and receiving signal to/from Pro Tools, no problem. I don't see any weird errors in the Dante Controller software.

I am using the Aurora primarily for hardware inserts, and am getting hundreds of ms of latency. In a total head scratcher, the channel that has the HW insert via the Aurora is showing back up in Pro Tools BEFORE the other session audio.

Any ideas on what might be going on here?
Yes it is working as badly as should be expected. There is absolutely no mystery about negative time offsets and H/W inserts. That happens when the actual insert latency is less than the ADC correction being applied.

Quote:
1) Should I use an external switch rather than the secondary port of the MTRX Studio for the Aurora?
I doubt that would make any difference.

Quote:
2) Could poor cables be the culprit?
No.

Quote:
3) Is Dante a poor choice for using with hardware inserts? I am aware of Dante's internal latency, and don't really care, so long as I can get everything properly sync'd (I have a small console for 0 latency monitoring/recording).
culprit?
Maybe. But the poor choice here is expecting this to just work, given the primitive mess that is Pro Tools H/W insert and ADC handling. You need to carefully measure and correct the latency on the insert tracks using the ADC +/- field on each track using an insert. I have written about that many times on DUC.

Quote:
I've been suing an old, 16-channel Aurora via LT-HD for about 15 years, and have *never* had any problems with latency, so this is a bummer. Wondering if I should switch back to LT-HD2 for the new Aurora(n).
And when you use DigiLink peripherals Pro Tools Ultimate uses hard coded latency data it has for the DigiLink interface (or the model emulated by the Aurora in this case) to make the ADC correction. And in this case relies on the Aurora having the correct latency of the HD I/O it emulates, not all third party DigiLink interfaces do.

I don’t know if when used via DigiLink the MTRX Studio emulation of DigiLink interfaces here has the correct latency for its internal analog I/O. Let alone there would be no way to make Dante with some unknown latency hanging off the MTRX fit into this fixed latency.

But here you are using Dante to the MTRX Studio and the Aurora, so the DigiLink fixed ADC do not apply and instead Pro Tools is getting an information about the interface latency via CoreAudio and the Dante Driver. As I’ve written about many times on DUC, even if the driver provides specific latency data for different IO paths for an interface, Pro Tools ignores that and just uses the latency for the primary I/O. I suspect in a Dante environment Pro Tools is totally unable to automatically deal with different latencies through different Dante peripherals/paths. But not a surprise, working as badly as expected, and you have to deal with this by measuring and applying a +/- ADC track correction. Or use a DAW better intended for use in professional environments like Logic Pro or Reaper with ping functions for adjusting HW insert latencies.
Reply With Quote
  #3  
Old 11-29-2023, 08:09 AM
mahler007 mahler007 is offline
Member
 
Join Date: Jun 2004
Posts: 330
Default Re: Massive latency b/t MTRX Studio & Aurora(n) Dante

Thanks Darryl,
I appreciate the response. I have fiddled with PT's various delay compensation features extensively, but with little luck. The amount of delay compensation PT is able to provide isn't sufficient to cover the latency I am experiencing, and I'm not really interested in pursuing anything other than a "set it and forget it"-type of solution.

I've also messed around with the various clocking options, including ones found here on the DUC, but to no avail.

Looks like I will probably revert to using an LT-HD2 card for the Lynx. Considering the previous one worked fine for 15 years, I suspect the newer one will as well (hopefully).

Best,
A
Reply With Quote
  #4  
Old 11-29-2023, 09:42 AM
Darryl Ramm Darryl Ramm is online now
Member
 
Join Date: Nov 2010
Location: USA
Posts: 19,657
Default Re: Massive latency b/t MTRX Studio & Aurora(n) Dante

You can use DigiLink, do you have HDX so you can connect all these interfaces via DigiLink. I would stay away from AUX IO.

If ADC is over correcting for insert latency then your adjustments would take away from the amount of ADC used, not push to exceed ADC limits. I would also hope you see latencies in the ms range so not an enormous number of samples, not the 100ms you are seeing--I would be curious how consistent this is. But then I have never done this with your setup and I still would not look to Dante for this (personally not a Dante or AVB fan outside of using it to reticulate audio around places).

If you do work through measuring this it hopefully is one latency measurement (for a given sample rate and h/w buffer size) you apply that offset to any track with an insert. Use a click on an audio track with an insert on the track with a straight through cable as an insert, and output that track to another track and measure the offset in samples and apply to +/-. You should be able to measure to one sample accuracy.

And while H/W inserts can usually be made to work OK with some adjustment, there are bugs in inserts and ADC at least for native processing (and I suspect hybrid is so flakey with latency issues I would avoid it), including one with LLM enabled, allow sends to persist in LLM, and a plugin before the H/W insert that will add multiples of 1024 sample latency. If there are bugs or unexplained latencies measuring them to a sample accuracy can help identify the source. Also make sure ignore errors is not checked, that introduces other timing issues.

Last edited by Darryl Ramm; 11-29-2023 at 10:46 AM.
Reply With Quote
  #5  
Old 11-30-2023, 04:29 AM
mahler007 mahler007 is offline
Member
 
Join Date: Jun 2004
Posts: 330
Default Re: Massive latency b/t MTRX Studio & Aurora(n) Dante

Thanks again, Darryl.

I went back to square 1 last night after discovering I had stupidly entered some values in PT's i/o hardware insert delay fields and then forgotten about them. Needless to say, this completely messed up all of my diagnostic work.

Starting over, I did a loopback test using a hardware insert via my Aurora/Dante combo, and determined I was 139.06 samples out of whack at 48kHz (Eventide Precision Time Adjuster was very helpful in determining the exact value). This translates into 2.9ms.

I entered 2.9ms into the hw insert delay fields in the i/o setup, and now everything is working perfectly. That seems like a pretty reasonable amount of latency!

Still not entirely sold on the Dante arrangement, and probably won't be until I spend some time working on some projects. I'm not going to be too keen on using it if different plugins create additional timing problems, or if there are other inconsistencies. In that case, I'll probably revert to using an LT-HD2 card instead and sell the Dante. If it's a simple as maintaining the delay values, and I never have to think about it again (save for different sample rates), I'll probably stick with it.

I am interested in using Dante as I want 64 channels of Digilink I can configure and route in DADman, primarily for Atmos workflows. Dante seemed to be the best option for getting that while also providing the amount of i/o I need for my outboard gear (not crazy about ADAT). I also have some digital outboard that would seem to be conveniently adaptable for use on a Dante network.

We will see how it goes — thanks again for your help.
Reply With Quote
  #6  
Old 11-30-2023, 11:01 AM
Darryl Ramm Darryl Ramm is online now
Member
 
Join Date: Nov 2010
Location: USA
Posts: 19,657
Default Re: Massive latency b/t MTRX Studio & Aurora(n) Dante

Oh great you got that sorted out. I wish I had just said 100ms sounded way too wrong in the first post. You are not the first person to leave wrong values in the IO insert delay offset page. Done that multiple times.

With Dante having more latency than Pro Tools is expecting here you can get away with just setting the delay value in the IO insert delay offset page.. But this is all broken, you should not be needing to set anything there (it should be only for correcting the latency in outboard digital processors used in inserts), all this should be handled automatically. For many other interfaces/setups the adjustments need to be made in the tracks ADC +/- field (and manually added or removed as inserts are used) because the offsets may be negative or just so small that working in samples is easier/won’t drive you insane as fast.

Lots of things need improving here, from the useless/confused Avid documentation, support for interfaces that do offer up different latency values for different IO ports, better/clearer support for manual adjustments where needed and especially a ping function like the serious leading DAWs have. And multiple ADC and latency related bugs fixed.
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
MTRX Studio + Lynx Aurora - use Aurora for Atmos outputs? mahler007 Pro Tools | MTRX & MTRX Studio 7 02-25-2024 06:26 PM
Dante latency with MTRX PT_NOOB_CH Pro Tools | MTRX & MTRX Studio 6 05-22-2023 05:16 PM
Dante SRC on MTRX Studio ViciousLullabyz Pro Tools | MTRX & MTRX Studio 4 02-04-2022 03:00 PM
MTRX Studio using Dante only c-tone Pro Tools | MTRX & MTRX Studio 15 08-20-2021 02:00 PM
MTRX Dante latency stuck at 1ms LukeHoward Pro Tools | MTRX & MTRX Studio 1 02-19-2018 11:13 PM


All times are GMT -7. The time now is 09:02 PM.


Powered by: vBulletin, Copyright ©2000 - 2008, Jelsoft Enterprises Limited. Forum Hosted By: URLJet.com