845 SET amps excel with Definitions. Lots of choices driven by your budget. The 845 drives Definitions energetically, with bass definition appropriate to the speaker's deep response. There are significant differences as you climb the price ladder, but at any given cost stratum, an available 845SET amp will outclass a push-pull tube amp of similar power, or a PSET 300B on Definition 1.5, 1.9 and 2.0. You'll get wide dynamic range, SET subtlety in details, superior tone density and serious drive.
I use Audion Black Shadow mono blocks. They aren't inexpensive. But as you go lower in price, Mastersound, DeHavilland, Sophia, Tri, Dared, Melody and upstart Asian brands give you plenty of alternatives.
You then have ability to tune via tube selection. Input and driver tubes are influential, but since most of these amps are supplied stock with the cheap 845A tube, an upgrade to the affordable 845B is usually in order. The new Shuguang Psvane 845 may be an upgrade too.
Phil