Help me make sense of these ADC readings ...

[Drew Mazurek]

Post the session, no audio.

[DJ Hellfire]

Impossible to tell without seeing whats on the audio tracks.

[YYR123]

He wants to inspect the routing,

[DJ Hellfire]

Yeah, that's what I'm saying. How the audio tracks are routed, what sends are on them, if they are sending to multiple aux's, etc. Example, if he has an audio track sending to both 9-10 and 11-12, I'm sure that would probably cause some issues being that 11-12 is also sending to 9-10. Just a theory.

[katerkarlo]

Originally Posted by latweek

Some people report that changing their buffer size under the audio engine settings and then changing it back does some kind of reset. You may want to just try that if you haven't, as well as closing and re-opening or restarting your system when you make changes to the audio engine, just to ensure they are taking effect and see if it makes any difference in your analysis of the delay values.

Will try that. Usually I stay away from the buffer size setting because changing it doesn't have any effect. I need to close PT and do the changes in the RME control panel for them to have any effect.

[katerkarlo]

Originally Posted by JFreak

Are these all routings you have in your mixer? The delay comes somewhere, but it's hard to see where.

I will post a screenshot of the other channels. What's bothering me is not the total session delay. There is one channel on which I have a couple of UAD plugins. They cause a lot of delay. What's bothering me is that some of the fx channels don't seem to be compensated enough. How can it be that the one channel with the UAD Lexicon 224 on it is not compensated at all?

The routing in this session is very simple. And the ADC readings on the audio channels all make sense. Plugin delay plus ADC always adds up to 5874.

I have a feeling it's just that the ADC values are not displayed correctly but ADC actually works fine. Otherwise the fx returns would sound totally off.

[katerkarlo]

Originally Posted by DJ Hellfire

if he has an audio track sending to both 9-10 and 11-12, I'm sure that would probably cause some issues being that 11-12 is also sending to 9-10. Just a theory.

The lead vocal track is sending to both a reverb (9-10) and a delay (11-12). And that delay is sending to the reverb. I don't see how this could cause any problems. Besides, when I removed the send from the delay (screenshot 2), not much changed.

[ZEUSS]

Originally Posted by albee1952

The 1% where I have an issue, it has always been an AUX send that has no destination(but it is a very different issue than this one and is obviously audible)

This is the issue thats been confirmed. Stay away from freezing auxes and leaving the sends or using any kind of bussing with no destination. Like routing multiple aux inputs to a bus and using the bus to record to an audio track...

[katerkarlo]

Ok guys, here are the screenshots of the entire session. Very simple. Only 1 output. No hardware inserts. Who can solve the mystery of the ADC readings?



Maybe I can contribute something myself. Today I set up a test session with 2 audio channels and 2 aux fx channels. I added some plugins and routings and realised how quickly it becomes difficult to keep track of ADC values.



Picture 1 is very straightforward: Aux 1 causes the most delay: 2306 samples. Every other channel is therefore delayed by 2306 samples minus its own delay. The sum of all ADC readings is always 2306.



On picture 2 it gets more complicated. Now Audio 2 (which has a plugin causing a delay of 62 samples) is routed to the fx channels. The total delay of the session should therefore equal 2368 samples. This is correctly reflected in the ADC reading of Audio 1. BUT: the 2 aux channels don't display the additional delay. Their ADC readings remain at 2306. I'm thinking this is a fault, as the fx channels should also be compensated by the additional 62 samples.



On picture 3 it gets interesting. Now Aux 2 is sending to Aux 1. That increases the total session delay to 3540 samples (= 2306 + 1172 + 62). Again, this is correctly reflected in the ADC reading of Audio 1. But again, the 2 aux channels don't show this additional delay!

To sum it up, I still believe the readings on the aux channels are wrong but the ADC process works correctly. I set all the fx signals to dry only so I could check if they are phase accurate with the signal coming from the audio channels and the absolutely are.

[JFreak]

Could you please make some music while wondering about this?