192 Analogue Outs Out of Phase

[sleadley]

I have 3 192 Interfaces feeding from 3 Genex 8 Channel A to D's via the Digital interfaces, I am monitoring back through a Neve 88R

and have discovered that the analog card that is connected to the option expansion bay is out of phase with the rest of the outputs

on the other 2 192 inrterfaces interfaces. We have checked the phase at the D-connectors at the rear of the 192 and it is definately

incorrect for this single output card the other 2 cards in the other 192's are fine. I am at a loss to know how this might happen or

how to fix the problem. We have simply phase revrsed the outs for the moment and all is well at the console, but I am very

suspicious. Is there a switch on the cards that changes from pin 2 to pin 3 Hot? Or something else. Any help would be appreciated.


best regards
Simon L.

[mixx]

not sure where the prob lies but did yo check the polarity pre converter? i am new to pro tools and phase is the bigest issue i have with alot of common stuff.. [esp when dup tracks] ,scariest issue with PT esp when dealing with plug ins and sub mixes inside a drum submaster,,

as an old school tape guy ..we always turned on tracks one at a time to access phase issues..every time a plug in goes in into an idividual track inside an already aurally approved multi source close miked summed domain...ummm scheit happens..this is the one main thing working in this environment scares me about...ya gotta always go back and listen after putting in plug ins regardless of delay comp..ears are final acessement..amd infintesimal time coherence balances really affects your summed common source output

[sleadley]

Yes the pre converter was checked, it is definately the 192 outputs as we put a phase check audio file into pro Tools and sent the out to all outputs and all were OK except the 1 set of 8 outputs.
S.

[DigiTechSupt]

We just tested this here and are not seeing the problem. If you move that card to a different slot, does the problem follow the card or does it remain with the slot?

[sleadley]

As we are in the middle of Mixing the music for the film we cannot remove the card for test. I have phase flipped all the outputs from that card and all is OK. I will check the 192 in 2 weeks when we finish the mix and see what is happening. I just wanted to know if there was a reason that you knew about.
Thanks
Simon L.

[Rail Jon Rogut]

Simon

I searched the DUC and found this thread -- did you check 192 revisions?

Rail

[RobMacki]

Simon

I searched the DUC and found this thread -- did you check 192 revisions?

Rail

wow

So thevault asked for a serial # or rev and no response...
How, or should I ask, was this ever resolved and how do you know if you have a unit with a potential delay issue??
I searched the answerbase but found nothing.

[sleadley]

Thanks Rail,
So before I did this gig I checked with Digidesign Australia that there was not going to be any reasons for this to be a problem, as this is a big film. So it seems like this is the likely problem as my units are quite old (nearly 3 years now) I was pretty sure that I had checked the firmware recently but will not swear to it.
This is are bad problem. I had checked the Answerbase (Kudos to Rail for finding the thread that pertains to this) but found nothing. This really should be noted. I had to phase check 140 Pro Tools out puts to figure out what the hell was going on here. Not fun even with the Neutrik phase tester. Not a great way to spend 4 hrs at the end of a long day.
Simon L.

[Jonathan Wales]

How exactly are you testing the phase.....

Is the signal generator plugin involved at any point. If it is, you must use a MONO sig gen track, then multi-assign (CTRL-select one output, then the next then the next so it's simultaneously coming out of more than one output) the output to individual mono outs on the interface. If you use a multi channel sign gen, or do the outputs any other way, then the actual sig gen output is known to have phase problems of its own.

[sleadley]

We used the Nuetrik NL1 Test unit with a recording of the test signal sent to all Genex and 192 Outputs.
Simon L.