Cinema Sound 3000 : 4000 : 5000 : High Powered Screen Arrays : ScreenArray Systems (2 way) : ScreenArray Systems (3 way) : Subwoofers 4000 Series : Surround Systems       4645C 4645C Single 460 mm (18 in.) Subwoofer System   Spec Sheet The JBL Model 4645C is a high quality subwoofer system, featuring an advanced technology 460 mm (18 in), low frequency transducer mounted in a direct radiator, bass-reflex enclosure for smooth response to the lowest audible frequencies. The 4645C is ideal for low-frequency augmentation of either analog or digital soundtracks in motion picture theaters and for general sound reinforcement applications. Features :   Specifications : 800 Watts Continuous Pink Noise, 1600 Watts Continuous Program Power Handling Usable response to 22 Hz (-10 dB, no EQ), flat to 22 Hz (-3 dB) with External EQ 2242H SVGTM Super Vented Gap Cooled Driver – High Sensitivity – Minimal Power Compression – Highest Maximum-SPL Capability – Extremely Low 2nd and 3rd – Harmonic Distortion – Symmetrical Field Geometry SFGTM – Magnet Structure – Extended Excursion Capability Approved by Lucasfilm, Ltd. for THX® installations   Rated Impedance   :   8 ohms Minimum Impedance   :   7.2 ohms Power Handling Capability   :   - Continuous Pink Noise   :   800 watts Continuous Program   :   1600 watts Peak Power   :   3200 watts Output Capability   :   - Axial Sensitivity   :   50 Hz to 500 Hz; 99 dB, 1W @ 1m 40 Hz to 100 Hz; 97 dB, 1W @ 1m Power Compression   :   - At -10 dB power (80 W)   :   0.6 dB At -3 dB power (400 W)   :   2.0 dB At rated power (800 W)   :   3.3 dB Net Weight   :   63 kg (138 lbs.) Dimensions H x W x D   :   1010 mm x 674 mm x 450 mm 39¾ in x 26½ in x 17¾ in