I brought my kemper stage to a rehearsal & used it into the fx return of a solid state Marshall. The other guitarist had a Mesa Mark III & it sounded a lot better. I had the same problem I always get with solid state amps; beyond a certain volume all I get is more treble. Sounded horrible.
I’ve also tried it in a 1 guitar band into a H&K Switchblade tube amp & it was a lot better.
For rehearsing with a band using traditional gear; is it wise to use an FRFR set-up or is it better to go with a tube power-amp & speaker? Basically use the kemper as a pre-amp so as to blend in with the band?