Wharfedale WLA-28SUB Passive Flying Subwoofer - 2 x 15"Since the launch of the WLA 28 line array, people have been expanding their systems into monster sized rigs. As these rigs have expanded, the demand for even more bass has also increased. The new WLA 28SUB now delivers that enormous bass for larger WLA systems all in a physical enclosure that fits perfectly with flown or ground stacked WLA 28 systems. With DUAL 15 Wharfedale Pro drivers boasting 4 voice coils, the WLA 28SUB is capable of 145dB and