Main Features: Samurai PRO Pioneer Reference for Open Show Size30 cm TypeSubwoofer Maximum power3500 W Continuous Power Output1800 W Frequency response20 Hz to 200 Hz (In-Car) Sensitivity88 (1 W/In-car) dB Impedance1 Ω or 4 Ω Dual Voice Coil (DVC) Mounting Depth154 mm Woofer Cut-Out HoleΦ352 mm Woofer materialPaper SurroundUrethane SpiderPolyester Fibre Voice Coil type4-layer Long Copper Voice Coil bobbin typeAluminium TerminalsPush MagnetsFerrite 38cm / 15″ Recom. Enclosure [l]57 (Sealed Enclosure) 90 (Ported Enclosure) Recom. Enclosure [ft3]2.01 (Sealed Enclosure) 3.18 (Ported Enclosure) Weight11.7 (Excluding accessories) kg DimensionsΦ405 x 216 mm AccessoriesSubwoofer mounting screws Thiele/Small Parameters Qts0.8 Fs [Hz]27.1 Hz Vas [ft3]2.69 Vas [l]76.20 Xmax [mm]22.8.