Pioneer Pro Audio XY-115S Bass Reflex Subwoofer - 15" (Black)15 bass reflex subwoofer Key Features High power subwoofer with an 15 inch, low frequency driver. Capable of reproducing deep bass as low as 45 Hz without distortion. Strong pillars installed in the cabinet ensure rigidity against the most powerful bass. Requires an active crossover to set the necessary frequency range (presets can be provided from Pioneer for combinations using the Pioneer XY 122,XY 101 and XY 81). NL4 INPUT and LINK OUT connections