Differential Drive®
Enhanced Performance & Dramatically Reduced Driver Weight
Differential Drive technology delivers better heat dissipation, lower power compression and higher dynamic range versus conventional single-coil designs.  In addition, magnetically saturated pole-pieces and an aluminum shorting ring significantly reduces nonlinear distortion.

Patented Differential Drive® Dual Voice-Coil & Magnetic Gap neodymium-magnet cone transducers
Engineering Precision Delivers Higher Power and Better Performance
JBL engineers wanted to solve the persistent challenge of all professional audio applications: how to increase performance while reducing overall system size and weight so that touring sound companies and working sound engineers alike could deliver unparalleled performance with their systems while reducing overall handling, transportation, and setup costs. The solution was a creative reconfiguration of the basic elements of the low frequency driver. Heat sinks are integrated into the driver's cast aluminum frame, and the neodymium magnets are placed inside the driver's dual voice coil assembly, completing the magnetic circuit without the heavy surrounding steel structure of conventional drivers. While dramatically reducing driver weight, all critical performance parameters are greatly enhanced: frequency response, power output and distortion. The resulting sound quality is extraordinarily transparent, even at very high SPL, while system weight and physical footprint can be reduced by as much as half when compared to conventional speaker systems. JBL's exclusive dual voice coil, dual magnetic gap Differential Drive technology is now at the core of a full range of woofer models incorporated in many JBL loudspeaker systems from touring sound and fixed installation, to studio and cinema sound.