@christianb5s4 "interested in an amp that offers a bit more refinement in the midrange and treble."
While I run a tube preamp when paired with my Pass/Forte’ Class A amp, and yes it sounds nice, and we also understand what your JC5 amp is, I’m wondering what you feel your XP22 / JC5 combo is missing now with midrange and treble?
i.e Is it too detailed/grainy or too soft/veiled over, or what’s going on that you don’t care for,...and now have the itch to buy another amp or another preamp. The JC5 is no slouch and neither is the XP22. Maybe there is another way to get you "there".
In other words what is "more refinement" to you - can you share a little more?