is it true that if you have two of the exact same subs, in identical boxes, and they get the same power, that having two only adds 3dB as opposed to having 1 sub? if so, is that a noticable difference?
no. i mean like say you have two identical subs, and two identical amps. One amp, for one sub. how much louder would that setup be compared to one of those amps going to one of those subs?