Let me add this: my system photos feature a few of an ARC amplifier - a vintage VT100 purchased from a friend last year. It’s been hot rodded with new caps plus kt 120’s and sounds very good in my set up - better than I had expected! But it has two issues: a fan which I dislike ( audible) and it’s a PIA to bias (never mind the cost of replacing 16 tubes …). Hence my thinking a more modern, easier to deal with tubed unit might do the trick.
Anything preowned would of necessity be bought without an audition in my set up and thus it’s a bit of a guessing game.
Other suggestions welcome and thank you!