Tube amp for Sonus Faber Extrema?

I move to my pair of Extrema with a Krell KSA-300s power, and really sounds great, great bass, the best midrange that you can hear and above all realism, incredible musicianship, I doubt any current Sonus, sound of this way.
A greeting Adrian

I tell you my experience, require a power Extremely high power and excellent quality, and combine with a wire handle cran amount of current and of good quality, I to mine the probe 1 with a Krell KSA-50S and the sound was really unfortunate that gave, now when you buy the Krell KSA-300s is another world, I realized there that have absolutely crosover current applicant, in short all the electronics associated with these speakers should be of high quality, in order to maximize the enormous potential of a once achieved, is obtained to get the most complete musical nirvana!
Greetings Adrian