Spdif and main out, parallel use

  • Hey guys!
    Haven't really found an answer to my question so I'm opening an new thread.


    Has anybody ever tried to record the spdif signal and main out (mono) signal in parallel?


    Usually I'm splitting the main out signal (mono) after the kemper in my patchbay in order to feed a distressor while tracking in parallel.
    that works fine, same DA/AD conversion for both paths. No phase issues etc..


    Now Im thinking... why not use the spdif out since I really like the stereo feel of 'space' and a few other fx. No loss, no extra conversion.
    And then also use a main out signal in parallel into the distressor.
    But now Im facing phase problems in monitoring AND recording.
    Of course that makes kinda sense to me since one out is being routed analog and one in digital directly.
    But in direct monitoring through RME total mix? shouldn't that be in phase? without different timing?


    In the DAW it says the difference is 28 samples. Of course I can drag one file onto the other or use a phase plugin, but how do I know which timing is the right one? The spdif or the analog ?
    Is there a way to solve this or am I totally out of mind and this setup is just made to fail?;))


    thanks for your thoughts on this!


    best

  • Thanks Nakedzen!


    Yeah, you're right about the first one being the correct one. haven't looked at it this obvious way. funny tho if the first waveform is the analog one.


    In a perfect world id like to mix both paths while monitoring/recording. But that doesnt seem to work

  • I record both the main out (wet) via SPDIF and also a mono DI track via the direct out. I mainly use the DI for 'insurance' or to reamp but a couple of times I used them both in a mix using a Scuffham plug on the DI. I didn't notice any phase issues at all but I was using the two tracks more like an artificial double track panned about 10:30-2:30 so any timing discrepancy might have played into the overall effect I was going for.


    I'll take a magnified look at some tracks but my main out is always wet so I'm not sure what that would tell me.

  • Yeah, that would be interesting @philbrown to see if your two recorded takes differ as well in timing.
    when you say wet you mean wet only 100% fx or dry with added fx?
    if its wet only then yes, that wont result in phase issues or timing problems.

  • Yeah, that would be interesting @philbrown to see if your two recorded takes differ as well in timing.
    when you say wet you mean wet only 100% fx or dry with added fx?
    if its wet only then yes, that wont result in phase issues or timing problems.

    Yeah I meant dry + wet - the stereo mix with FX.


    I had a look and I'm seeing the stereo mix signal approximately 19 samples AHEAD of the DI.


    EDIT: This could be the result of the way my Apollo interface processes SPDIF and analog signals.

  • Not what I expected either @cbee, but the SPDIF is already digital and the analog has to go through A/D conversion so that may explain it. IOW it may not be a Kemper issue at all., just converter latency. I guess we'd always be comparing apples and oranges with the digital/analog issue.