Again, thank you for your insightful replys and useful links.
I understand that this is a Strange need to have. And actually, it is not for myself, but for the other guitarplayer in the band. I am hoping to convince him to join “the Dark side” but he has some reserves. We use in Ear monitoring and wish to turn down the level of noise on stage. The guitarist in question plays a tube amp. Aside from the general issue with turning the volume down without taking the juice out of his amp, in 1 song his guitarpart relies heavily on feedback. So now this 1 song is determining the stage volume of his amp.
This is a problem also with a mic’ed amp, because if he turns the volume up in that 1 song, it becomes louder in FOH, but even worse - it gets distributed louder to each in ear mix.
Without a kemper - the ability to turn up stage volume (in order to achieve the desired feedback) without affecting the in ear mixes - you need to replace the mic with an attenuator that has xlr out with Cab sim. These can be quite expensive.
So, in order to convince the guitarplayer in question, i have to find out whether this can be done on the kemper.
It seems that with a midi knob, the same use as an attenuator will allow, is possible, but with the added flexibility of the kempers features.
I hope this explains my strange, but specific need.
thank you for your inputs.