Alphasonik PSW915, 38cm (15") Alpha Mayhem 900 Series Subwoofer, 2500W RMS 38cm (15") Alpha Mayhem 900 Series Subwoofer 2500W RMS, 5000W MAX, impedance: Dual 2 Ohm frequency response: 30Hz - 900Hz 200oz. Magnet, sensivity: 98dB @ 1w/1m aluminium machine cut basket