18” forward-firing, with 4” voice-coil. 1Ch DSP and 1Ch amplifier are required.

18” forward-firing, dual gap motor structure - 2 inner and 2 outer voice coils, neodymium motor. 1Ch DSP and 1Ch amplifier are required. Min. recommended amplifier: 72 Vrms, 102 Vpk, 18.0 A; equivalent to 1100 W @ 4 Ω

21” forward-firing, dual gap motor structure with 2 inner and 2 outer voice coils, neodymium motor. 1Ch DSP and 1Ch amplifier are required with this subwoofer

21” forward-firing sub, dual gap motor structure with 2 inner and 2 outer voice coils, neodymium motor. 1Ch DSP and 1Ch amplifier are required.