Plus 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 MMD dome 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. Unipivot - To ensure proper imaging the 52.7i utilizes a patented rotating tweeter (patent no. 6,002,780). So even if the speaker is mounted down low in the door, the soundstage can be brought up and optimized for the listener's location. Woven glass fiber woofer cone material is extremely stiff, minimizing cone flex which yeilds very low distortion and improved clarity, an Infinity trademark. SLI high-output design. Conventional 4-ohm speakers do not leverage allof the power available from today's car audio amplifiers and high-powered head units. This topology extracts every last watt from the amplifier source, increasing overall system output and efficiency. Computer-optimized voice-matched outboard passive crossovers - Each Kappa multielement and component system features an outboard crossover that has been voice-matched using audiophile grade air core inductors and polypropylene capacitors. The result is flawless performance with incredible detail and accuracy. Adjustable tweeter level-Each Kappa multielement features a user adjustable tweeter level control. On the two-way models, simply rotate the tweeter to add or subtract 3dB output. On the three-way models, it is the simple push of a button right on the tweeter faceplate.