MC 275 tube amps with what speakers ?

I have read (never heard) that Eggleston Works Andras sound good with these amps (search this and Speaker forum). While I have not heard this specific combination, I will say that the Egglestons are among my favorite speakers. While I own and love the Andra's little brother, Fontaines, I have heard the Andras (previous version) and would upgrade to them had I the funds. Good luck with your pursuit.

Sonus Faber Elipsa SE's. Wow...what a combo that would be.

uhh...definitely not Planar speakers. I've owned 4 pairs of Planars and they love power.

ditto on the sf se's

I have 2 MC 275 mkV. I use them in mono configuration to drive the top end of my Infinity RS-1B's. Plenty of power in my 16 X 26 room.

Rick (RWD)

For over 20 years I ran a pair of Mac MC 275 Gordon Gow Commemorative Edition amps strapped in mono into a pair of Martin-Logan Quests, a hybrid electrostatic with a 48” x 18” ‘stat panel and a 12” woofer in a sealed enclosure.  Room was 16’ x 22’ with a vaulted ceiling.  No problem whatsoever ever in driving that difficult load and the sound was glorious.  FWIW,  I was only on my second set of output tubes when I moved and sold the system, and they still met spec.