The DAP NRG-15S is a passive subwoofer rated at 1600 watts peak (400 watts continuous RMS). It uses a 15” woofer with a 3” voice coil to deliver bass down to 50 Hertz (-6 dB). With a sensitivity of 95 dB/W/m, it comfortably produces up to 121 dB continuous and up to 133 dB peak.The rugged, lightweight plywood enclosure has an M20 threaded insert for mounting a speaker pole. It uses 4-pole speaker in and thru connectors and offers an additional 4-pin terminal connector, which is particularly useful for fixed installations. To get the most out of the NRG-15S, we recommend using a 4th order high-pass filter at 45 Hertz and a 4th order low-pass filter of up to a maximum of 450 Hertz