Infinity REF 9613I 6"x9" three way loudspeakerPlus One woofer cones - This patent pending technology deliver a cone with more surface area than competing models of the same size. The result is increased bass output and higher efficiency. Edge-driven silk-dome midrange and tweeters - These are not commonly used W-domes, but fully edge driven domes like those found in fine home audio loudspeakers. This much larger voice coil increases power handling and provides better sonic integration with the mid-woofer.Infinity Reference® has been engineered to deliver best-in-class performance for those looking to replace or upgrade their factory speakers. Features like Infinity’s Plus One® (patnet pending) woofer cones and edge-driven-dome tweeters have helped position Infinity Reference as the number-one line of automotive loudspeakers for the past six years straight.