Harman's patented (US patent #7,548,631) Plus One polypropylene woofer cones provide increased cone area of up to 35% by moving the attachment point between the surround and the frame outward. The benefit of this technology is an increase in overall efficiency by up to 2dB. This provides superior output and performance when used as an upgrade to a factory system and also for a pure aftermarket system with outboard amplification. Close attention to fitment is paramount to the success of this speaker family. The super-rigid vented baskets help to cool the voice coils making for a reliable speaker. Not only do these look cool but they provide a real world benefit by wicking heat way from the motor structure almost like a fan as the cone moves through its stroke. The benefits are lower distortion at high output levels, a longer lasting speaker and higher power handling. For most brands, off-the-shelf speakers and a cursory approval of frequency response curves are good enough. That's not the case with JBL. This is just part of an extensive development process undertaken by some of the best transducer engineers in the world to provide the finest listening experience at any price point.