JBL SRX728S Dual 18″ High-Power Passive Subwoofer

The JBL SRX728S is a powerhouse subwoofer system designed for professional sound reinforcement in large venues, clubs, and touring rigs. Featuring two 18″ 2268H Differential Drive® woofers with neodymium magnets, this front-loaded, vented enclosure delivers thunderous low-end extension down to 27 Hz, with a peak SPL of 136 dB. Engineered for maximum output and minimal distortion, the SRX728S incorporates large vent areas to reduce port turbulence and a heavily braced birch plywood cabinet for tight, accurate bass response.

Its switchable input modes (+1/–1 or +2/–2) and parallel/discrete wiring options offer flexible integration with a variety of amplifier setups. Whether you're running it in cardioid arrays or as a standalone sub, the SRX728S delivers clean, earth-shaking bass that’s ideal for live concerts, church sound systems, and mobile DJs.

Key Features

• Dual 18″ 2268H Differential Drive® Woofers with neodymium magnets for high output and low distortion

• Frequency Response: 33 Hz – 220 Hz (±3 dB); usable down to 27 Hz (–10 dB)

• Power Handling: 1,600 W continuous / 3,200 W program / 6,400 W peak

• Maximum SPL: 136 dB peak @ 1 m

• Nominal Impedance: 4 Ω (parallel) or 8 Ω × 2 (discrete)

• Input Modes: Switchable +1/–1 or +2/–2 via external switch

• Connectivity: 2 × Neutrik® Speakon® NL4 connectors

• Enclosure: 18 mm, 13-ply birch plywood with black DuraFlex™ finish

• Grille: 16-gauge steel with acoustically transparent foam backing

• Dimensions (H × W × D): 602 × 1,067 × 838 mm

• Weight: 76 kg (166.5 lb)