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.
