If you don't mind DIY you could install a Tangband 1772 driver in a sealed box and supplement it with a tweeter (both crossed over properly to avoid comb filtering). Its 97dB and in a reasonably sized box (bigger bookshelf) would go to 45-50Hz.
I'm doing exactly this right now for a set of monitors in my electronic music lab at home. The amp driving them makes 5 Watts (class A PP tube amp; much cleaner than an SET of similar power) plenty in the room I'm using.
Any smaller speaker like this will need a sub.