best pre/amp to match my Elipsa

I am an amateur so forgive me if I ask stupid questions. I have a pair of Sonus Faber Elipsa speakers (with Rel B1 sub) and need help to choose pre and amps. I currently have Bryston BP 26 and 4B SST and have also tried Krell HTS/KAV 3250 for multichannel music. To my untrained ears, i though krell's midrange was much better (even for 2 channel) but couldn't tell other differences. I listen to 70% classical music (big orchestral, vocal, piano, violin), prefer having multichannel capability so I can occasionally listen to SACD or watch movies without having to have two systems. Bryston BCD-1 and Oppo 83SE as source components. my budget: $5k-6k for both (used price). Thanks. Ron