A used ARC VT100 MKII is almost a "no brainer" IMO at around $2K used. It's rated at 100wpc but is probably conservatively rated. Lots of power to drive "most" speakers. It's probably more neutral sounding than "Tubey" sounding. A used VTL ST-150 is another good idea. Also, a used C-J Premier 11 is a sweet amp, but only 70 wpc. I don't know how much power your speakers need however?
On the other hand, if you want to save $$, & can really get along on 70wpc, a used VTL ST-85 for hopefully less than $1000, depending on age, can be a really good deal. It has kind of a "classic, tube amp" sound IMO, as opposed to the more neutral ARC sound. Maybe you should really think about how much power you need? There can be a huge difference between tube amps rated at 70 wpc vs. 100 wpc. (Count the # of output & driver tubes for a start). And I'm guessing that VTL is something you should check out given that you want a "liquid" sound--Good luck!
On the other hand, if you want to save $$, & can really get along on 70wpc, a used VTL ST-85 for hopefully less than $1000, depending on age, can be a really good deal. It has kind of a "classic, tube amp" sound IMO, as opposed to the more neutral ARC sound. Maybe you should really think about how much power you need? There can be a huge difference between tube amps rated at 70 wpc vs. 100 wpc. (Count the # of output & driver tubes for a start). And I'm guessing that VTL is something you should check out given that you want a "liquid" sound--Good luck!