Summary: Type: subwoofer; The number of bands: 1; Power: 1000 watts (maximum); Housing: no; Additional information: Recommended amplifier power: 50-1000 W. Nominal impedance: 2 and 4 Ohm. Resonance frequency: 30 and 31 Hz. Diameter mounting hole: 280 mm Massive double design of the magnet. Massive copolymer cones. Balanced suspensions.; ...