Profiling a system with delay (latency)

    i'm sure this issue has been addressed and responded to before. Maybe things have changed in recent firmwares....


    What are the know side-effects for profiling an amp (modeller) that has some form of delay or latency?
    ie, if someone attempted to profile a VST amp that had, for example, 100mS latency (very extreme case)
    I understand that time-based effects are not recorded as part of the profile process (ie reverb) but as extreme latency is effectively a delay in the signal chain does the profiler compensate?
    its not something i plan to do but curious to know how this affects users, or should i say the profiles created, on such systems.
    There may be some players who perhaps you want to transfer their favourite VST amp setup to a live situation.

    Quote from slateboy

    Thanks for the quick reply, @IngolfHave you done it before or maybe know what the highest latency (longest delay) permissible is?

    Yes, I think I profiled my Scuffham S-Gear years ago, but I couldn’t be bothered to pursue this further.
    I think there is no longest permissible delay.
    Even if you distant-miked your amp from across a big church or a big hall all delay and reverb would automatically be removed

    Quote from Ingolf

    ... if you distant-miked your amp from across a big church or a big hall all delay and reverb would automatically be removed

    And that's basically the "problem" because that's not 100% true. :)
    Only the time component of the delay and reverb will not be captured. The sound component of reverb and delay though will be captured.


    But regarding the OP's question:
    The Profiler will tolerate "some" latency. Don't ask me for exact values but with excessive latency the Kemper Profiling would stop the process.
    If I find the time, I will do some testing. But if you run your interface at relatively low buffer settings, it should work.

    Quote from lightbox

    And that's basically the "problem" because that's not 100% true. :) Only the time component of the delay and reverb will not be captured. The sound component of reverb and delay though will be captured.


    But regarding the OP's question:
    The Profiler will tolerate "some" latency. Don't ask me for exact values but with excessive latency the Kemper Profiling would stop the process.
    If I find the time, I will do some testing. But if you run your interface at relatively low buffer settings, it should work.

    ?
    Perhaps I was exaggerating a bit, but the removal of any time based information (e.g. as with room miking) is exactly the reason you can‘t create a profile that contains time based room information.
    Please elaborate.

    Quote from Ingolf

    Please elaborate

    as I said before, the time component will not be captured. But the sound of the reverb will. You made the example of a distant miced amp in a church or big hall. The amp will generate lots of huge reverb with plenty of highcut that fills the room and will get captured by the distant microphone. Will make the sound fatter. even a delay effect once it gets less accentuated and a bit more washed out will contribute to the sound component received by the distant mic. It's just that the time component will not be part of the sound. It will not have the delay effect but certainly the delay and reverb sound mixed with the amp sound.


    In simple terms:
    If you profile close miced it sounds way different than far or even distant miced ... because of the room sound that gets into play more the further you go away. :)


    The results can be quite strange. The sound has some fat, huge, dark character but at the same time it's totally dry because the time component (of delay/reverb) is missing. You can't compensate easily by just adding some reverb on top because the added reverb again will add not only time but also sound components to the mix.
    In an extreme example it can get really weird because the sound feels like a HUGE amp captured in a big hall or church but you want to just add some room or plate reverb, you start feeling something's not right. It's quite tricky to actually use distant micing for profiling with good results. :)

    Quote from lightbox

    as I said before, the time component will not be captured. But the sound of the reverb will. You made the example of a distant miced amp in a church or big hall. The amp will generate lots of huge reverb with plenty of highcut that fills the room and will get captured by the distant microphone. Will make the sound fatter. even a delay effect once it gets less accentuated and a bit more washed out will contribute to the sound component received by the distant mic. It's just that the time component will not be part of the sound. It will not have the delay effect but certainly the delay and reverb sound mixed with the amp sound.
    In simple terms:
    If you profile close miced it sounds way different than far or even distant miced ... because of the room sound that gets into play more the further you go away. :)


    The results can be quite strange. The sound has some fat, huge, dark character but at the same time it's totally dry because the time component (of delay/reverb) is missing. You can't compensate easily by just adding some reverb on top because the added reverb again will add not only time but also sound components to the mix.
    In an extreme example it can get really weird because the sound feels like a HUGE amp captured in a big hall or church but you want to just add some room or plate reverb, you start feeling something's not right. It's quite tricky to actually use distant micing for profiling with good results. :)

    Oh, we're in total accordance then. I didn't imply anything else.
    A distant miked source with the distance substracted will sound very strange of course.
    But the OP's question was if it’s doable, and well, yes it is. ;)

    FWIW, I just profiled my UAD SVT powered plugin that has an annoying amount of latency in Presonus Studio One 3.5. I figured I'd give it a shot to see what happens.


    It was actually kind of strange. I could hear the latency when switching to the source amp which is expected. But after profiling and comparing the Kemper to the source I could STILL hear the latency on both. I thought maybe it didn't work after all. But after saving the profile and switching to browse mode there was no latency in the profile at all.


    Makes it nice to be able to track with that sound again, and with even LESS latency than a plugin.


    I'm new and still figuring out the Kemper, so maybe I'm doing something dumb. In the end it works, though.