Pair Kicker 51KSS6904 6X9" Car Audio Component Speakers w/1" Tweeters

The KICKER KSS6904 is a 6x9" two-way component system: separate woofers, separate 1-inch silk-dome tweeters and an in-line crossover for each side. Splitting the tweeter out of the woofer lets you put the highs on the sail panel or A-pillar, which lifts the soundstage to eye level instead of leaving it down by your ankles.

Four tweeter mounting options come in the box: flush, angled, surface pod and coaxial. The last one is the useful trick. The woofer bullet-style phase plug unscrews and a supplied adapter takes its place, so the tweeter rotates and tilts from the center of the cone. That turns the system into a high-end coaxial when the door is the only spot available.

Woofers use internally dampened polypropylene cones with rubber surrounds for controlled midrange and midbass. Rated power is 15 to 150W RMS at 92 dB sensitivity, with frequency response from 35Hz-21kHz. Mounting hole diameter is 5-5/8 by 8-7/16 inches and bottom mount depth is 3-3/16 inches, so the woofers sit behind factory grilles in most doors. Woofer grilles are included for door locations where the cone would otherwise sit exposed.

The crossover body is small enough to hide in a door cavity or behind a kick panel, and high-frequency attenuation of 0, 4.5 or 9 dB lets you pull tweeter level back in a hard, reflective cabin. Common installs include a front-stage upgrade in a commuter sedan, a two-way front with a subwoofer behind the seat in a truck, or a full active build where these handle everything above 80Hz.