■ Double 15" subwoofer system ■ 15” voice coil neodymium magnetism subwoofer at compact design. It can response quickly and powerfully. ■ Firm steel grille protecting the loudspeaker from outside force impact. ■ The enclosure uses high-density plywood and firm finish to protect it from friction and collision. ■ It can go with full range loudspeaker as LF energy compensation.