I use Tannoys 15" Time compensated 3838 drivers in my GRF Memory reflex cabinets, these are rated at 92db anachoic and 95db domestic sensitivity.
My room is quite small 3.85 x 3.5 I drive these speakers effectively with either a Nick Gorham 300B Set Monoblocks (9watts/ channel) or a Bel Canto Set 40 (37 watts / channel)
Nicks amps sound glorious in the mid and high frequency range but the Bel Canto has it in the bass region very much as you would expect.
In summary I think SET amps can work with these speakers but as with all things Hi Fi the amp / speaker combo has to be tailored to your own room. I am sure in a large 6m x 6m lounge both these amps may struggle but in my room they are lovely.
Analogue
401 / PU7 / AT33ev
Longdog Audio Quartz turntable PSU
Longdog Audio MCJ1 - Prototype Phonostage
Digital
Innuos Zen Mini Mk 3
Topping D50s
Caiman Seg & Dorado
Cambridge CXC
Amps
Tron Seven Linestage
Bel Canto Set 40 or Nick Gorham built 300B Set Monoblocks
Speakers
Tannoy GRF Memory.
Tannoy ST100.