Anticab (live cab compensation)

  • It would be really great if you could make it so that playing the Kemper through a normal guitar cab or similarly colored cab could be made to compensate and sound more like the source material, so you don't have to disable the cab section.


    My idea for this is if you could profile your output cab and it's poweramp, and then have the KPA apply the inverse of it's settings to the output EQ for you (or maybe as a more complex "Cab" model applied in negative against the inbuilt cabs) basically it would compensate using the "output profile".


    Admittedly it would result in it incorporating the microphone in that compensation profile, but I think even with that it would be much closer to how it should sound, or at least close enough as to solve the problem.


    (this comes up in relation to the thread talking about how all of the clean amp's profile is in the cab section, so obviously you don't want to disable that in a live setting).

  • This sounds to me like a greatidea, especially, in the sense that it applies "profiling" idea to the problem, which is the main capability of the KPA. As an engineer myself, I am not sure it will be easy to implement though. Some kind of change in the cost function may be needed, if any optimization is being performed in the system identification (profiling) process.


    Jake

  • although the inverse cab approach might seem feasible, all I can say is that it isn't as simple as that.
    basically, there is no way you can make a heavily colored speaker system (like a guitar cabinet) all of a sudden become 'flat' by applying an inverse of itself.

  • There are limits to what you can do, you can't go where the speaker and amp cannot go, but you can at least smooth out the result for a given tolerance and frequency range, which may be quite enough. I'm not suggesting that you can claw back frequencies beyond the cutoff, but that the Kemper could set it's output EQ section to compensate subtractively far better than a human ear could.

    Edited once, last by Per ().

  • Distortion or clipping shouldn't come into it (you'd have to be playing at pretty insane levels to even encounter speaker breakup), this would only need to modify the EQ curve. Most cabs are anything but flat in frequency response across their range, e.g. :


    [Blocked Image: http://home3.netcarrier.com/~lxh2/CELV5C1.gif]


    You can compensate against that by using EQ to reduce the fairly major bump between 400-800 and 1.5k to 6k and maybe raising the lower frequencies a tad, you wont end up with a hi-fi speaker and amplifier, but you will end up with something that sounds truer to the source. You could alternatively reduce the same frequencies within the Cab section of the Kemper instead, so still leaving the rest of the simulation intact, but giving you a sound that's a little closer to what was originally intended.

  • I use studio monitors, but many people don't, and even if they do then live they still want to play with an amp behind them and be able to interact with said amp/cab.

  • True. OTOH, the "studio monitor" experience is (to my ears at least) a different beast from the "stage active cab" (like an RCF) one. I mean, the active cab is to me more "amp like".