Home Slickdeals Monolith THX Ultra 12″ powered subwoofer. $639.99 w/free shipping. Slickdeals Monolith THX Ultra 12″ powered subwoofer. $639.99 w/free shipping. By ARCOM - 8 July 2019 156 0 SHARE Facebook Twitter Go to the deal page: Monolith THX Ultra 12″ powered subwoofer. $639.99 w/free shipping.
