About a decade ago I was running a pair of stacked (2 horns per side, rated around 106dB) Oris150 horns with custom bass cabs. I rolled through about a half dozen low-powered amps including 2A3, 45, 300b, etc. All good amps from reputable manufacturers. It wasn't until I switched to a 200w Lyngdorf TDAi2200 that those speakers actually started to sound good, actually very good. I had the TDAi2200 on the horns, digitally linked to a TACT power amp driving the bass cabs, and it sounded great. Don't be afraid to experiment with SS amps, they'll need to be dead quiet though, as the Lyngdorf unit was/is.
More recently I've used a Lyngdorf TDAi 2170 on Altec Valencias and VOTT A7s, and it has worked very well, particularly using its crossover function and of course the room-perfect software.