Upgrade Carver to Tube Carver question.

I have a nice rebuilt Carver TFM 45. It's dead quite. I have Focal Kanta 3s & a PS Audio BHK preamp.  No vinyl just a Rotel CD player & streaming for now.  Aside from my mediocre sources what improvement could I expect from a Carver 275 or the 350 tube amp?  Room is 16x25 if it matters.