I'm a little confused about the speaker cabinet efficiency issue. For instance, I'm an upright player in small combos, mostly jazz or church liturgy gigs using a 30 yr. old, carved German bass and Underwood p/u. I think I want either a Low B-1 or Epifani UL-110 for my Clarus III but I've read that Low Bs are not that efficient. I assume this means I will need more power or have to turn up the volume knob on my amp to get the same sound output as another cab that is more efficient. Right so far? I recently acquired the Clarus III and for now am running it through one of my Carvin PA cabs (Model 822, 12", 8 ohm). I like the amp a lot. It sounds clean and undistorted at all volume levels so far. The volume control on the amp has never been turned higher than the 10 o'clock position. The range begins at the 7 o'clock position and goes around to the 5 o'clock position. Until I've experimented with different cabs I don't know if this Carvin PA cab is efficient or not. I'm wondering where or when this efficiency issue is going to affect the sound, if at all. I rarely ever have to double and if I do, it's always been a low-volume kind of gig. No loud bands or wild drummers. An occasional big band but most of the time the volume requirements are not high. I'm coming from 15+ years of using a 15" Polytone Mini-Brute III with a Fishman pre-amp. Any comments or shared experiences are much appreciated. Thanks much.