HDX Delay Compensation and Aux tracks

[skylab001]

I’ve noticed when in standard HDX mode when recording a live input that signals sent to Aux tracks are not perfectly aligned with delay compensation. Let’s say I’m recording a guitar and have an FX send bussed to an Aux track with an echo on it(I’ve used both soundtoys native or Mcdsp native & aax DSP), and the echo is a synced 1/8th note. The echo will not be in time while input monitored during recording, but when I switch off live input and playback the track, it syncs up. I’ve found I need to turn off delay compensation on the aux track while the track is input monitored for it to sync while recording. This seems like it should happen automatically. Is there something I’m doing wrong or is this “just the way it is”?

[devinemke]

I am having what I think is the same/similar issue. In my case I am doing large Post mixes for Film/TV and and have an imported video file with it's embedded audio. My mix is routed through a series of auxes to create 4 x 5.1 stems, then headed to 4 x 5.1 stem print tracks, then to a composite 5.1 print master track. When all the print tracks are in input (while mixing) the summed audio is out of sync with the video embedded audio (which is headed directly out of the session monitor path) but when playing back (printed) everything is perfectly in sync. I thought the ADC engine would accurately compensate for this.

My rig: Pro Tools HDX (3 cards) 2024.3.1 Ultimate running a Mac Pro 2019 macOS 13.6.6

[BScout]

Originally Posted by skylab001

I’ve noticed when in standard HDX mode when recording a live input that signals sent to Aux tracks are not perfectly aligned with delay compensation. Let’s say I’m recording a guitar and have an FX send bussed to an Aux track with an echo on it(I’ve used both soundtoys native or Mcdsp native & aax DSP), and the echo is a synced 1/8th note. The echo will not be in time while input monitored during recording, but when I switch off live input and playback the track, it syncs up. I’ve found I need to turn off delay compensation on the aux track while the track is input monitored for it to sync while recording. This seems like it should happen automatically. Is there something I’m doing wrong or is this “just the way it is”?

It is operating the correct way (and the way it has always worked.) The point is the least amount of delay for the player. If it was delay compensating the input/record track, it would add latency. So while input monitored or in record, that track does not delay compensate.

If you want to work against this, you can put "auto delay comp" into blue mode (right click the lower delay comp box on the Mix window for the track and you will get this option.)

[BScout]

Originally Posted by devinemke

I am having what I think is the same/similar issue. In my case I am doing large Post mixes for Film/TV and and have an imported video file with it's embedded audio. My mix is routed through a series of auxes to create 4 x 5.1 stems, then headed to 4 x 5.1 stem print tracks, then to a composite 5.1 print master track. When all the print tracks are in input (while mixing) the summed audio is out of sync with the video embedded audio (which is headed directly out of the session monitor path) but when playing back (printed) everything is perfectly in sync. I thought the ADC engine would accurately compensate for this.

My rig: Pro Tools HDX (3 cards) 2024.3.1 Ultimate running a Mac Pro 2019 macOS 13.6.6

You need to put those tracks into blue mode. Blue mode was specifically created for post-production people who need stem and full mix tracks to always align (where there's no issue with delay because you aren't recording an instrumentalist live.)
This is not a fault -- things are working correctly.