The JBL SRX828S 18″ Dual Passive Subwoofer is a portable subwoofer in the SRX800 series from JBL Professional. It has been designed to deliver class leading performance in a variety of applications including small and medium sized installations and tours. When used in conjunction with the SRX800 full range systems and other SRX800 subs, the JBL SRX828S 18″ Dual Passive Subwoofer is an integral part of a high performance, fully configurable loudspeaker system.With indexed feet and a lightweight design, the JBL SRX828S 18″ Dual Passive Subwoofer can be configured for a variety of applications, including being stacked in a cardioid configuration for large shows on stage.For incredible extended low frequency response, the JBL SRX828S 18″ Dual Passive Subwoofer uses an 18-inch woofer with JBL’s patented Differential Drive Technology for reduced weight while maximizing power amp efficiency. 3” voice coils and dual ferrite drivers deliver exceptionally low distortion and extended low frequency response.The JBL SRX828S 18″ Dual Passive Subwoofer is supported with tunings for Crown I-Tech HD amplifiers, which can be controlled as part of a comprehensive system with Harman Audio Architect.With best in class 18mm wooden enclosures, 14 gauge steel grilles, and JBL’s Patented DuraFlex finish, SRX800 speakers are built to last and withstand a lifetime of hard tour use. TechnologyPURPOSEFUL DESIGNEvery detail in the SRX800 Series was purposefully designed and thought through with full consideration for its intended use. Ergonomically designed handles support an easy, non-fatiguing grip for streamlined handling. M10 suspension points, indexed feet, and pole/tripod mounts support a wide, flexible array of configurations.TRANSDUCER TECHNOLOGYJBL’s patented Differential Drive® Technology ferrite drivers incorporate 3″ voice coils with lower mass ferrite magnets for reduced weight, increased power handling, exceptionally low distortion and extended low frequency response. JBL’s 2432H is the only neodymium 3″ voice coil compression driver in this class, delivering very high power levels and smooth, crystal clear sound.ApplicationsLive performance systems.Mobile and fixed DJ systems.Sound system rental and tour.Permanent installations.SpecificationsSystem TypePassive dual 18”, subwoofer systemMaximum SPL Output129dB (Continuous), 135dB (Peak)Frequency Range (-10dB)30hz – 150hzFrequency Response (-3 dB)47Hz – 120HzSensitivity98dBSystem Power Rating4800W Peak, 2400W Program, 1200W ContinuousNominal Impedance4 OhmInputsNL4 Input, NL4 Loop-thru (+/-1 or +/-2 Selectable)Operational ModesPassiveLF Driver(2x) 2279HCrossover Frequency80hzEnclosure18mm Duraflex coated plywoodCastersAccepts JBL WK-4S KitHandles8FinishObsidian Duraflex™ finishGrillePowder coated, Obsidian, 14-gauge perforated steel with acoustically transparent black cloth backingDimensions (H x W x D)681mm x 1205mm x 574mm (26.79in x 47.42in x 22.57in)Weight137.0 lbs (62.1g)Shipping Weight147.0 (66.5kg)