Turn up the volume with this BIC America Formula F12 powered subwoofer, which offers adjustable crossover and volume, as well as automatic on and off, for ease of use. The Venturi vent prevents noise from the ports from spoiling the rich, clear sound.
This is a great subwoofer for the price point. It has the ability to interface between your mains or run from a RCA cable direct from you amp (If amp is equipped). Its quite powerful as I have the volume at about 40%.