I’m interested in the Schiit class A amp. Any thoughts on compatibility with GE TRefs.. Listening room 20X18 with 10’ ceilings. Current amp is 70X2 Carver tube amp and it has more that enough power. Thoughts please….

Well as far as the brand and value for the money , I think you're looking at the right piece of gear.

I have their yggdrasil DAC.

To your question about compatibility, I would say that it certainly would be compatible. However, the question you have to ask yourself is how loud - decibel wise - do you typically play back music. If you stay in the very low 90s (db) or ideally lower, 20 watts would be plenty (IMO), including the extra "headroom" that every amp needs. If on the other hand you're playing in the high 90s or above , then I think you might want to consider an amp that has more wattage.

Thought: as GHAL stated, Is 20 watts enough? Buy one Aegir. If that's not enough power, buy a second one and use as monos...80 watts.

I'm running a Decware Zen Torri mk4 tube amp rated at 25 watts. It sounds best in the 80-90 db range, but will play in the low 90's. The majority of my listening session's are with a solid state amp and tube Preamp. I like the bass performance and added headroom that this combination provides.