@normantaylor Since you went from 450wpc to 2000wpc, isn’t it possible that’s the reason for the improvement you described? It may have nothing to do with mono vs stereo.
Stereo or monoblocks
I recently bought a pair of the JBL HDI-3800 speakers. I also own a McIntosh C-2300 preamp. Should I buy a used McIntosh mc402 stereo power amp or try to find a pair of a different brands monoblocks? The new Schiit Tyr has my interest.