PMC PMC8 SUB - Active 8-Inch Subwoofer for Conventional or XBD SystemsThe PMC8 SUB is a true low frequency reference monitor which extends the bass response of your speaker system, imparting more of PMC's signature ultra clean, ultra fast low end to any setup. The PMC8 SUB can be used as a compact stand alone subwoofer within conventional multichannel systems, or as an XBD cabinet, creating a full range PMC6 XBD midfield monitor. When used in this way, the dedicated 'XBD' DSP mode marries the speakers and sub unit