just a small 2 cents, most of you know much more than I.
I drove an 86db speaker to comfortable levels (in a small room) with a 10 watt Baby Sophia. The sound was wonderful.
I now have a Rogue that would drive the cones right out of the boxes if I'd let it and it's only 55 watts. But......love it as I do, the small room gets hot, hot, hot and it's wintertime now.
FWIW