Fletcher-Munson Compensation for 2.0 Profiles

1st Official Post
    The Profiler Model referred to in this thread is ...
    ☑️ Profiler Stage

    I’ve read several times now that unfortunately it’s not that easy to dial in the new 2.0 profiles so that the highs still sound good at higher volumes. Sadly, I’m affected by this problem as well. When I tweak the profiles through my in-ears or studio monitors, they sound amazing. But once I play them louder in rehearsal or live, they become very shrill very quickly.

    Of course, I could set up the profiles directly at high volume, but that’s not really practical for home use. And when I turn the volume down again, they become dull very quickly.

    It would be great if there was a separate control in the Output section for each output, with a knob to compensate for the Fletcher-Munson effect — basically a dynamic EQ that could be adjusted quickly and easily. Unfortunately, I don’t have a free slot left after the amp to insert an EQ as an effect, and having it per output would be much more practical as well.

    Quote from Michael_dk

    Aren't the EQs in the output section PER output? And I believe the output settings can be saved as well.

    Yes, that’s true, but with the existing EQ in the output section it’s not possible to recreate such a complex EQ curve. It also changes the fundamental character of the sound quite noticeably.

    Quote from Radek01

    Florean That's interesting observation. I have to try it really loud. It wasn't there with v1 profiles, right?

    This effect already existed with the v1 profiles as well. It’s more of a physical phenomenon related to how frequencies behave at different volume levels. However, I feel like it’s much more noticeable with the 2.0 profiles. I’ve also seen several people mention it — including well-known commercial profile creators — saying that the new 2.0 profiles are more difficult to dial in properly in the high frequencies.

    Hey, this is Kemper. We can go beyond 1980's technology, one size fits all, who cares how loud that output device is anyway.

    Why not profile this dynamically and adjust the eq for the actual loudness and room?

    But why stop there:

    • Handle preset leveling of each preset to a reference target (crunch) at the current volume.
    • Store and recall the loudness profile per venue as a preset .. 100% selectable by mobile rig manager or midi.
    Quote from Bommel

    I like Loudness knobs ... the only sad thing is they have different curves at different "volumes" but a little bit of less 4k and so on would be cool. maybe if the eqs for the outputs were parametric we could build it ourself

    My approach would be to have a control for each output that adjusts the dynamic EQ curve. For example, a value of 5 could be the default, roughly representing the curve at around 80 dB.

    If you turn the control up, the curve shifts toward higher dB levels. If you turn it down, the curve shifts toward lower dB levels. In other words, it would function like a dynamic loudness EQ.

    Of course, it is probably not feasible to link this to actual real-world dB values, but I do not think that is necessary. It could still be adjusted live in a relatively simple and quick way.

    Quote from G String

    I'll move this to the general discussion. Share your approaches there please.

    Thank you very much for the official response. However, I actually thought this topic belongs here, since it is essentially a suggestion for a new feature to solve an existing problem. The fact that the thread has turned into a discussion/conversation does not really change the core request itself.

    May I ask how I should phrase it differently so that the topic can remain here? I’m concerned that otherwise it will simply disappear into the depths of the forum.

    Quote from Ruefus

    I’m pretty sure moving it to general is an indication of the likelihood you’ll see this feature.

    Pure speculation on my part.

    I'll go one step further and venture that you are spot on, and for good reason too.

    The Fletcher-Munson curve as we know it is an average of data collected from several participants a very long time ago. In reality, there were different curves for each individual. The curves they presented are averages of all the collected data.

    Such a feature would have to be individually adapted for each user. Just the process of finding "your" Fletcher-Munson curve would be a tedious process of playing sine waves at various frequencies and mapping your ears' sensitivity. Quick digression, but that would further beg the question of how granular you want to be. The curve is represented by like 10 different frequencies (or something), which only reveals the sensitivity to those exact frequencies.

    There is no feasible way to create what is being asked for. And if we "think outside the box", the best solution is much easier. Dial in tone at representative sound levels. Or do it once and take note of the amount of EQ you need to apply to make it sound good at loud levels, and just use that as a basis for new patches. That maybe sounds like an "imprecise" approach, but so would an averaged Fletcher-Munson curve EQ be.

    Edit: All right, when I think about it again I suppose you could make some kind of "attunement" process where you connect headphones and have sounds played at rising levels, and you press a button on the interface when you hear it, and it just calculates a rough curve for you, then apply that like a filter at the end of the process. But then that had me thinking about how your tones would be perfectly tuned to your Fletcher-Munson curve, but maybe not the audience's. Not that that's not the case already if you manually EQ your tone to whatever your preference is, but my overall point is that this is the kind of feature where no matter how you implemented it, it would be convoluted, technical, possibly resource demanding - but ultimately imprecise and a poor solution to a simple problem that already has a simple solution - using high/low shelf EQ to approximate the Fletcher-Munson curve in a rudimentary fashion and not worrying about all the stuff that's past the point of diminishing returns.

    Edited 3 times, last by Preacher (May 26, 2026 at 8:55 PM).

    I have really doubts if that could ever work. Nobody knows the level at your ear. What headphone are you using? what amplifier comes at which gain after the Kemper? etc.. I think if it is really the loudness itself, I do not understand the problem. Just play loud with headphones or your InEars at home and adjust it. But I think it is not the loudness - isn't it more the mix in the band, or the interplay with the acoustic in the room etc.. I think thats more complex.

    Quote from huibuh

    I have really doubts if that could ever work. Nobody knows the level at your ear. What headphone are you using? what amplifier comes at which gain after the Kemper? etc.. I think if it is really the loudness itself, I do not understand the problem. Just play loud with headphones or your InEars at home and adjust it. But I think it is not the loudness - isn't it more the mix in the band, or the interplay with the acoustic in the room etc.. I think thats more complex.

    Wow, what a brilliantly simple solution — just turn the headphones up at home and adjust it there. Problem solved forever. 😄

    Jokes aside, of course I understand that this is a very complex topic and that there is no way to achieve a perfectly measurable or 100% accurate result, because there are many factors influencing the sound. But the issue definitely exists, and I’m clearly not the only one experiencing it.

    In the end, such a control would obviously have to be adjusted by ear — just like the Pure Cabinet parameter, which is also basically simulating a certain effect rather than applying some scientifically exact correction.

    And regarding the other assumptions: I can rule out that this is caused by room acoustics or the band mix. The behavior is exactly the same whether I use in-ears, a PA, or nearfield monitors. It also makes no difference whether the band is playing or not.

    Of course it is possible to dial the sound in so that it works well live. But as I already mentioned, when I then play the same profile quietly, it sounds noticeably duller. And honestly, I don’t want to have to play loud all the time at home just to get the “right” sound. That’s exactly why I would appreciate a solution that allows me to keep essentially the same sound character across different volume levels.

    The reality of this is that it can be done.

    But it can’t be done effectively or anywhere close inside the Kemper or any other similar device.

    The compensation has to be calculated relative to actual SPL at your ears. Which the Kemper (or any other similar device) has no way of measuring.

    Everything downstream of it — the power amp, speaker sensitivity, room size, your distance from the cab? That all determines what level reaches your ears.

    There is no way for the Profiler (or any amp, for that matter) to know that.

    Can it be done? Yep.

    But not in the Kemper.

    Even then - only in fairly, if not strictly controlled environments. Where nearly the entire signal chain and your location are known and compensated for.

    My armchair research (and that’s all it is) says you’ll *never* sort it out in a dynamic environment.

    Too many variables, and they all matter.