I have a pair of Anat Ref II Studios. I am now running them with a Burmester 911 Mk 3 amplifier, connected in balanced mode by a Burmester silver XLR cable to an MBL 5011. The sound is quite good, but being a hobbyist I'm always looking for improvement. In the fall, I hope to try out other premaps. Three likely candidates are: (1) the Burmester 011, whch should partner well with my amp; (2) the MBL 6010D, which I imagine to be an improvement over the already good 5011; and a Halcro pre, which, based on previous experience, I regard as virtually a laboratory instrument. My musical tastes are largely classical, and I listen to CDs, SACDs, and FM radio, so a line stage is all I really need (the Burmester has phono inputs).