Re-Profiling The Profile For FRFR or on Stage

    I was telling a guitar playing, engineer friend of mine about the KPA today, and as he was trying to understand what I was explaining, he said: "...so, when you hook up to the FRFR you re-Profile that to have the KPA adjust the output to the tone curve that the FRFR imposes onto the originally Profiled amp?"


    I said, "No, but that's brilliant!" :thumbup:


    I realize that FRFR implies Flat Response, but they're all a little different. Also, sometimes there's a need to route through the front of a pre-existing backline amp. As long as you have a mic available, it could become a non-issue.


    It seems to me that you could play through any external amp and speaker combination and get an exact representation of the initial profile without having to try to tune it "by ear". Each new "rig" could then be saved for future use, i.e., RCF monitor, Mackie monitor, JBL monitor, etc.


    Please discuss this and help me to see why this would be a bad idea. :?:


    If it's a good idea, let's have CK add it to the list of firmware upgrades. Since I don't program things for a living, it seems like a simple thing to implement - after all, the profiling and saving process is already there. :D

    Edited once, last by Dlaut ().

    I must be stupid but I didn't understand what it is about..probably a language thing ... :)
    When you say external amp and speakers what kind of amps and speakers is that ?

    What ever you intend to play the KPA through (unless it's headphones).


    In industrial process design it's called a "feedback loop". It ensures that the output of a process equals a known standard (in this case, the original, saved rig profile) - otherwise adjusting the input (or other process factors) to cause the output to match.


    I'm not sure that you could make a crappy FRFR sound perfect, but the KPA could impose - dare I say it - a "Tone Match" using the original profile as a reference. Therefore, the actual amp and speaker being used for playback would be of much less consequence.


    This "Re-Profile" would only have to be done once for each external amplification setup, and then saved for future use.


    I see many people debating the merits of various FRFR speakers, and even external amps. This process could level the playing field. It would seem to be of even greater help when, as luck would have it, you were forced to play through a "normal guitar amp that had no external loop.

    Quote from BRUNO

    So let's say I play the Kemper through RCF monitors ( which I do) ,tell me exactly how you would procede cause I'm still not sure..sorry it's late here :)

    You would hook up the Kemper just the same as if you were profiling a guitar amp (including a mic on the RCF), except that you have already selected a "rig" to play through. The difference - if it were programed to do this - is that you would go through a "Re-Profiling" process where the KPA would compare the existing rig profile to what's coming out of the RCF and apply a corrective curve to the profile to "adjust" the selected rig (the ideal sound according to the KPA) to the *new reality* of what is coming through the RCF.


    Now, RCF speakers are pretty flat to begin with, so the corrective curve would be more subtle. There are many other speakers (and amp combinations) where that is not so much the case. And, it's not the case at all with regular guitar amps that some are forced to use - say on "fly dates" where your normal equipment package is inconvenient or impractical to bring along.

    So if I understand well first you want a take a profile ,then spectrum analize the set of monitors you used to profile..may be that's what you call reprofile ..then do the same analize to any set of monitors you plan to use , compare and correct ? That would a kind of tonematching yep but I don't see how you could do it while profiling unless the software gets a serious update
    Also to profile the profiler you need two of them... May be something could be done to the profile mode so it could just analize the monitors themselves and then apply a tone match based on the reference monitors used on the original profile


    Then if some "toneprint" could be done for the reference monitors and the destination monitors it would be possible to hear the profile like the OP did BUT the room makes as much if not more difference ;)

    Edited once, last by BRUNO ().

    I think that the concept is similar to the "Correction IR" one that you can find in the FAS forum.
    Basically what you suggest is to implement a post amp "corrective profile", usefull to correct the FRFR eq curve.
    I think it's not that easy, since you need a perfect flat mic to catch the eq curve of the FRFR.
    Somewhere in the FAS forum there's a thread about taking a corrective IR by using a behringer mic (plus a corrective EQ to flatten it).

    Quote from ballantine

    Isn't this request similar to mine?
    Output eq presets


    may be ..anyway You're no supposed to have to tweak more the profile at it's first stage cause it should sound how you wanted it to sound in your own monitors and is supposed to be reproduced in other monitors...so trying to narrow the differences between several sets of monitors used in studios and live would be a good idea.But adding some EQ to tone match the original is exatly what the KPA does first thing IMHO

    Quote from Per

    And mine from a month before that : Anticab (live cab compensation)


    I missed it because I was not registered to this forum... I didn't own a KPA :)


    Maybe, as the super moderator said in your thread, it's almost impossible to correct a guitar cab and make it sound like another one (some frequencies are missing and you can't create it :-))
    But in my experience it's not so hard to correct a FRFR monitor and try to attenuate some bothering resonance.


    An example: my KPA sounds really amazing in a pair of Martin Blackline F12 (with dedicated M3 controller and Crest Audio CC2800 power amplifier... the best I tried!) with almost no-adjustement. I tried with RCF or Mackie and it doesn't sound as good as with the F12, but I can improve the sound adjusting the EQ (especially under 500 Hz) to eliminate resonance on some profile...


    I know, I can do these adjustment manually using my ears and the EQ on the mixer and/or in the Master Ouput of KPA (and that's what I do), but in my mind doesn't sound so complicated to implement an automatic output equalization... this machine already has a mic input and the ability to make those "alien sounds" during the profiling.... :thumbup:


    I hope that my new hero (Mr. Kemper... Christopher Kemper :thumbup: ) can think at this feature in a future update.

    I'd certainly like to have the option/ability to do this, and I don't see any particular obstacle to doing it either outside of the fact that it could only work for the frequency response range and it would need to be a subtractive eq to avoid clipping etc, which would mean you'd need to pump the volume up higher than normal (and all that goes with that), in order to get the same volume as before. But provided you don't mind a little higher noise floor and power amp workout then within those constraints it should just work.

    In a nutshell this is very similar to part of the eq portion of what some home theatre receivers do with auto-calibration. It would probably take some serious programming and a standardized mic.


    It really makes sense, given the KPA's nature that it would have the capability to do this when you consider how important the back end of this equation is. I've got to believe that somewhere during the process of creating the KPA that this sort of output eq auto-calibration crossed CK's mind.

    "Tone is in the fingers" is not a necessary response to anything that I might type on any internet forum threads. Thank you.

    Quote from BuckeyeBrown

    In a nutshell this is very similar to part of the eq portion of what some home theatre receivers do with auto-calibration. It would probably take some serious programming and a standardized mic.


    It really makes sense, given the KPA's nature that it would have the capability to do this when you consider how important the back end of this equation is. I've got to believe that somewhere during the process of creating the KPA that this sort of output eq auto-calibration crossed CK's mind.


    Great idea man. Somewhere i found a calibration procedure based on the behringer ECM8000 to correct the FRFR frequency response.