Evolution JL AUDIO ZR 650-CSi - Car speaker - 85 Watt - 2-way - component Top Of The Line! [GiGaFurniture & GiGaInternational] Ships only The Latest Productions. 6.50 in. / 160 mm Woofers; 1.0 in. / 25 mm Aluminum Dome Tweeters Continuous Power Handling: 85W Continuous System Efficiency: 89.5 dB @ 1W/1m, System Nominal Impedance: 4 ohms System Frequency Response: 48 Hz - 25 KHz  3 dB.