Infinity Kappa 123WDSSI Switchable Subwoofer

Selectable Smart Impedance (SSI): A switch on the input terminal allows you to easily change the woofer's impedance between 2Ω and 4Ω settings. (The connected amplifier should be off when changing the impedance.) The power handling is the same for either setting; 500 watts RMS/1500 watts peak. Cone: The cone material is a composite of glass fiber over a paper pulp material. Adding the glass fiber layer increases cone rigidity to improve bass accuracy, while the pulp base improves the sub's damping characteristics. Terminal: Although the spring terminals will accept bare wire up to 8-gauge, the angle makes inserting an 8-gauge wire very difficult. As a practical matter I consider these 10-gauge terminals. Sealed Box: Infinity recommends a sealed enclosure with an internal volume of 1.3 ft³. Sealed enclosures provide the most control over a woofer and provide accurate sonic reproduction, making them suitable to all types of music. Ported Box: Infinity recommends a ported enclosure with an internal volume of 2.5 ft³ with one 4" diameter x 10" long port, resulting in a tuning frequency of 35 Hz. They also recommend using a sub-sonic filter. Ported enclosures typically provide better overall efficiency than sealed so they are suitable for use with smaller amplifiers, giving you more bass output from a given amount of power. Free-air Mounting: In addition to being compatible with sealed and ported enclosures, the woofer can be used in free-air applications. A free-air subwoofer is designed to be mounted on a baffle board, which separates the front of the speaker from the back. For instance, you could mount this woofer to a board attached to the rear deck or placed in the trunk against the rear seat. The trunk acts as the enclosure housing the subwoofer. Because there is no specific volume of air to stiffen the suspension, the free-air power handling is approximately half that of the woofer in a box, in this case 250 watts RMS.