Just checking, how are you listening to the Kemper?
I normally play thru a 100 watt stereo into Behringer 2031P 8" monitors. The tweeters are very flat sounding. I dont normally play loud. And the overall sound of the Kemper is fine. But it does not sing or have much treble presence. It sounds a bit muted.
While working on the VST, I am on my programming PC which has Edifier 1280T 4" speakers. These speakers are not flat. There is a lot of low bass and crisp highs. Guitar sounds amazing on them. When playing the VST on these speakers it sings and has amazing presence like you are next to the amp. Really fun to play on them.
I have not spent enough time with the VST on the Behringers to get a feel for it.
Today, I pulled the Kemper up to the programming PC and played thru the Edifiers. It sang fine and was a blast to play. So some of the singing tone must be vibrations and feedback from these speakers. Even though I am not playing loud at all. But I was blown away by how much better it sang.
I keep making these posts about how important the crossover and tweeter are for guitar. The Edifiers sounds amazing. The Behringers... not so much. They of course have better bass and can play at much higher volumes. But the presence and sizzle of the tweeter is MIA.
I recently repaired an old Laney ProTube 50. It has a very nice Tube sound on the clean channel. Was testing pedals today on it. I will eventually test out the Kemper on it. I usually play thru a custom 2x12 cab I made with varying speakers in it. They get rotated. Eminence, Bugera, and Celestion 70 80.