Sound Labs. Maybe my vintage pair won’t last as long as something newer
and the newer ones will be compatible with lower powered amps, but I
sonically, I can’t ask for anything more. They leave all my prior
speakers and most others I have heard in the dust and it usually isn’t
that close. I could upgrade all other components many times over and I
don’t think the Sound Labs would ever be a weak link.
Did you get the update offered a few years ago? It makes the speaker a lot easier to drive (and it sounds better, but that is likely because the amp isn't working so hard).
(its also possible to modify the older crossovers pretty effectively and at very low cost; either way once done you can do with a 100 watt amp what used to take about 250 watts...)
My speakers at home are the Classic Audio Loudspeakers model T-3.3
They are 16 ohms and 98 db 1 watt/1 meter, with solid bandwidth from 20Hz (dual 15" Alnico magnet woofers) to 35KHz. The crossovers have 6db slopes and use Mundorf silver and gold foil capacitors. The midrange is handled by a custom compression driver that employs a beryllium diaphragm with a Kapton surround, mounted to a custom horn, electromagnetically powered. Its first breakup is at 35KHz; people often comment how "electrostatic" they seem as they are so fast and transparent, but I can drive them like crazy with only 60 watts.
These are some of the smoothest and most detailed speakers I've heard and some of the very few that with a single amplifier can get the bass right. They do all the things you want a speaker to do, and do it without the need for high power, although I find that in my room with my taste 60 watts is a lot more fun. I have a set of little 7-watt power amps based on the type 45 power tube but I really find that the extra power makes a pretty big difference. I like to play things in a lifelike manner and it takes a bit of power, finesse, dynamics and bandwidth to really get Wagner or Massive Attack really right.