I'm sticking to my original prediction that it's a custom version of the Celestion K12H-200TC, or maybe even the K12H-100TC.
Indeed, Ben, you may be right. However, I have to say that the statements and promotion by Kemper, in word and in print calling this a "full-range" speaker, are a bit peculiar, if this indeed a whizzer cone-based driver such as the Celestion K12H-200TC...because in no audio world that I know of would that be considered "full range". Heck, Celestion's own spec page shows frequency range as: 50-10,000Hz.
Now, don't get me wrong. I am sure CK knows what he is doing, and I am pretty confident that whatever speaker solution is used in the Kemper Kabinet will work just as he intends. But I find it a bit curious that he has a problem with the term FRFR, apparently only when it comes to the "Flat Response" part of the quasi-acronym. Seems to me, that he should equally have a problem using the "Full-Range" terminology, if this is a single-driver/voice-coil whizzer cone speaker based upon the K12H.
Note following link:
Whenever you switch to a full range sound, for an acoustic guitar the Kemper Kone will switch to Full range Mode automatically for you. Music that is fed into the Profiler through the Aux Input will also be played back in Full range Mode.