MC 275 tube amps with what speakers ?

I don't want to start a fight but Planar speakers with tube amps, even the venerated MC 275 are not the best plan.
Speaker choice is a subjective thing. You would have to tell us a great deal more about your preferences and even then we would be trying to guess what you would like most to be listening to. You see it is difficult at best. Are there any speakers you have heard that you were pleased/happy/delighted etc. with ? Perhaps we could think of similar sounding other manufacturuers and models.

Do you really have 18 ft ceilings?? What is you budget? What are your other electronics?

MM de Capo's from Canadian Company Reference 3A. Easy to drive, love tubes and sound fantastic!

Yes 18 feet tall, wanting the new Mc 275 and tube pre I have a great inside with Mc.for great price. 15,000 0n speakers