I have the same setup for my speakers as you. Grand Piano for the mains, the Sonus center channel, and the Concertino for the rear. I used to have the Concerto for the rear, but found the Concertino to work just fine. I know have the Concerto in a different system. I would not drive these speakers with a receiver, it will not do them justice. Seperates are the way to go. I am using the Proceed AVP, the Proceed AMP 2 and AMP 3. I have also driven this system with B&K separates and they sounded excellent. Check out the REF20 or 30 and the B&K five channel amp on the used market. You can probably find them for under $3000.00.
Best receiver for sonus f. Grand Piano under 3000
I am purchasing A pair of Sonus Faber Grand Piano, Center chanel and Concerto Home for rears. Would appreciate your opinons on best receiver I can purchase under $3000. B&K 307?; Marantz sr9200?;Pionner 49tx? I will also be connecting to sony 65xbr2 . Thanks