Nominal diameter 258/10 mm/inch Rated impedance 4 ohm Program power 180 watts Rated power 120 watts Sensitivity 89 dB Frequency range 30~1500 Hz Effective piston diameter 210/8.27 mm/inch Minimum impedance 4.2 ohm Voice coil diameter 51.5/2.0 mm/inch Voice coil material copper Voice coil winding depth 17/0.67 mm/inch The number of layers 4 Kind of layer Outside 4 layers Top plate thickness 8/0.32 mm/inch Cone material paper Cone design straight Frame material Fe