As bgavin already pointed out "Whether or not you NEED A0 is subjective, especially in a live mix." 27.5Hz is the fundamental of the lowest note that will go through this cab, yes. It's one whole step down from your average 5 string bass. 300W doesn't seem all that much to ask from a modern cab design either. When I mix music like this, I certainly don't need to have the bass rumbling at 27.5Hz for it to be audible and clear, I'm not sure why that would be different in a jam space. With my current rig, in the full mix setting, the lowest notes get a bit lost. You can still hear that there is bass, but which note is being played can be a bit unclear. I'm aware this may be due to room modes as well. Yes the room is treated but you know, it's no professional studio. I think that a low tuning is my second priority behind being a robust backline cab, and not nearly as important.