How would you power Wilson Audio Sasha or Alexia II?

Gryphon amplifiers.

From personal preference:

Luxman / D’Agostino / Ayre.


From what you should listen to if you can to form a personal opinion:

Pass / Ayre / Luxman

How about the preamp and power amp(s) you listened to when you auditioned the speakers?  If the music moved you, that is what you're looking for.

robert1976

How would you power Wilson Audio Sasha or Alexia II?

Which pre and power amps should I audition to find a match made in heaven? Total budget for pre and power amp(s) is $50-60k.

If you have that kind of budget, the VERY best for these speakers are either a
Gryphon Antillion Evo stereo
https://gryphon-audio.dk/shop/power-amplifiers/antileon-evo-stereo/

or the Antiilion Evo monoblocks.
https://gryphon-audio.dk/shop/power-amplifiers/antileon-evo-mono/

And take your pick for the preamp
https://gryphon-audio.dk/produkt-kategori/preamplifiers/

Cheers George

Definitely Luxman, Why? Luxman M900u has ability to double down to one ohm.
Both speakers you described have a reactive load. In other words, it’s all over the place and needs an amplifier that can handle the dips and peaks related to phase and impedance the load of the speaker has. Both Luxman M900u and C900u will run you $30000.