Pass labs krell parasound amps

I am going to throw in Schiit Tyr based on others reports.

McIntosh and Pass will both work well with your Revels. I had the 228be’s with both. I switched from Mac C53/MC312 combo to Pass XP32/X260.8 monos, mostly out of curiosity. The Mac gear is no slouch, despite a lot of haters out there. It is powerful, quiet, accurate, well built, and runs cool.

As others have stated, Pass has more depth, warmth, liquidity, better bass, and is less fatiguing. There is a slight lack of openness to the X-series which you should consider, however. There are always tradeoffs---the slightly veiled aspect of Pass is probably what makes it so easy to listen to for hours on end--it’s never bright or etched. This is particularly meaningful to me as I listen to a lot of Blue Note jazz. Pass takes the edge off. Running Mac, I had more days when I was one (side of music) and done. With Pass, I’m always tempted to play more---that matters.

I nearly went with the X250.8, but decided on monos. They run very warm as will the X250.8.

@OP. The X250.8 is a great amp. It should work well with your Levinson pre.

One other brand worth looking at is Sim Moon which might fit your sonic preferences well.

Nelson Pass has a long history of designing reliable  & wonderful amps.  I owned a 
Threshold 4000 for 25 years before selling it and buying the X250.8.  Yes, they run hot & yes, the X250.8 does have the "Pass " sound, which makes it very easy to enjoy and live with.  Once you own it I cannot imagine an unhappiness UNLESS you are one who continues to compare A to B....on its own it is great....additionally, you will be hard pressed to find a company with better customer service, though I doubt you will ever need it...

Personally, I would stay away from Krell until they get their house in order due to the loss of one of their founders.

Pass and Parasound are bullet proof with excellent customer service.  I have no experience with Mac.