SSI™ (Selectable Smart Impedance) Most car audio system designs call for 2- or 4-ohm impedance. Stadium subwoofers feature an exclusive dual impedance switch that lets you choose either load impedance option. Not available from any other manufacturer, SSI lets you reconfigure your system by simply flipping a switch. Aero-cooled voice coil The Stadium voice coil significantly increases power handling and improves reliability by going with the flow – of air. The woofer’s motor channels air pumped by the cone movement past the voice coil, and the voice coil former exposes the coil’s inner and outer surfaces to the airflow. This aero-cooling design is unique among aftermarket subwoofers. Oversized voice coil The three-inch (75mm) voice coil proves you don’t have to be a heavyweight to pack a serious punch. It handles more power than conventional two-inch voice coils, yet it’s lighter than four-inch voice coils. It strikes the perfect balance between thermal power handling and low mass. Premium screw-down terminals Power is the lifeblood of any subwoofer. The terminals on the Stadium accommodate up to 8-guage wire (8.37mm2 cross section), which transfers low-resistance, low-loss power to the woofer, even over long wire runs. This ensures the subwoofer – and your music – has the power it needs.