JBL SRX728S Dual 18 Subwoofer Features:

* High-power subwoofer
* 2 - 2268H Differential Drive, neodymium magnet, 18" woofers
* Power Rating (Continuous/Program/Peak): 1600W/3200W/6400W
* Front-loaded vented enclosure
* 2 Neutrik Speakon NL-4 connectors
* External switch selects either contacts +1/-1 or +2/-2
* Internal connector separates each woofer into 2 channels
* Birch plywood construction
* Heavily braced
* Rugged DuraFlex finish
* Isolated chamber for each woofer
* CNC machined, 16-gauge steel grille
* Frequency Range (-10 dB): 27Hz—220Hz
* Frequency Response (±3 dB): 33Hz—220Hz
* Input Connection Modes: Switchable, +1/-1 or +2/-2; Internally selectable, Parallel or Discrete
* Recommended Crossover Frequencies: 80Hz, 24dB/octave HPF; 80Hz, 24dB/octave LPF
* Power Rating (Continuous/Program/Peak): Parallel: 1600W/3200W/6400W
* Maximum SPL: 136dB SPL peak
* Sensitivity (1w @ 1m): 98dB SPL
* LF Driver: 2 x JBL 2268H 18" Differential Drive woofer with neodymium-magnet and dual voice-coils
* Nominal Impedance: 4 ohms parallel; 8 ohms x 2 active discrete
* Enclosure: Rectangular, 18mm, 13-ply birch plywood
* Finish: Black DuraFlex finish
* Grille: Powder coated, black, 16-gauge perforated steel with acoustical transparent charcoal foam backing.
* Dimensions: 42"W x 23-3/4"H x 33"D
* Net Weight: 166-1/2 lbs.