hmm - interesting - different distortion curve - lack of odd harmonics?
At the end it does a matter with pure sin waves when you cannot hear the differences with real guitar spectrum?
you might not be able to hear it directly , but i think it would make a difference in percieved thickness of single notes and i would think kemper would match a sine wave response input because when it profiles it can test for that , sending a pure sine wave test tone is the easiest of tests. hope that was just a glitch in thier test .
maybe ill try to test this myself , mostly because i struggle to get a thick lead sound and i hope its not because of this and would need to be fixed in a fw update