Infinity Reference 9623i 6 x 9-Inch Three-Way Loudspeaker (Silver/Black) Plus One woofer cone technology gives improved bass response over conventional speaker designs The Edge-driven textile-dome tweeter gives outstanding high frequency performance The speakers are designed to be driven with a 2 ohm amplifier or head unit; this will give you improved bass response Polypropylene Woofer Cone for improved bass output The speakers can be driven by a factory deck as wells as an aftermarket head unit