Considering buying new amp s

I do plan to keep the Revels. I would like to stay under 3500.00. I'm fine used.

Have always been a tube amp fan (30yrs), so recently had Atma-sphere m60 mk3, MFA 200D's and Bel 1001 to play with.
Chose the Bel, sold mfa's, sent m-60s for update. Go figure!
Always wondered why Bel had cult-like following, found out.

Op, how much are you willing to spend? are you open to more suggestions?

It all depends on your speakers since this is the critical interface. Are you keeping the Revel's? If so, assess their amplification demands and then choose from a shortlist of amps that will mate correctly with your speakers. If not, put off the amp decision until you are into speakers that you like and are going to live with for a while. Not knowing answers to these questions nor your budget you might consider the Modwright KWA100SE or the KWA150 (or the SE version of the 150 which is moving up another price point). Good luck!

I would recommend Pass X250.5 very nice smooth tube like sound. More bass punch then the Mac.

Did you like the sound of the Butler if so the logical move is to get a 2 channel Butler.
Otherwise you could with that vague request and fairly large budget go down the "amp of the month club" until you find the one you want.
However if you always coveted the McIntosh, and they have that appeal, then satisfy your Mc yearnings and try it. I have a small older one which synergizes well with my Klipsch Vintage speakers (I have lot of speakers) but didn't find it's sound that appealing with most others. Just MHO of course YMMV etc. etc. A newer more powerful one may sound very different... as I said etc.