Following up on my previous post about upgrade expectations and with respect to 'Arnoldhasmail''s post: I have yet to go down the upgrade path for the Ref 9 V2 SE precisely because of a felictous experience with 'tube amps'. I recently mated a Prima Luna Prologue Three with the NuForce monos and discovered pretty much all I can reasonably expect from a two channel music system. A marriage made, well, not in heaven, but right here in my listening room. Both the Bryston BP26 and the Nuforce P-9 are enjoying a break from hard duty.
This was the motivation behind my thoughts about system synergy, on the one hand, and our experience of music, on the other. Each time a change in the system is made, upgrade or otherwise, reeducation of the ear - i.e. the brain - takes place. The question is whether sometimes, for aesthetic reasons, the education fails to take hold.