The MG-118SUB is an 18" active subwoofer system powered by a powerful class a/b amplifier coated full metal grill. The cabinet features an 4" voice coil 18" Woofer and pushes 1600W of Power. The built-in amp module has multiple features including Dual (left and right) Combo input jacks (XLR/1/4"), Dual (Left & Right) XLR Signal Loop Through, Phase/Invert Switch, Low Pass Filter adjustment knob and a Master Volume Control. This sub bass system is an ideal solution to any PA application where additional low frequency is required.