For almost two years I've been using my old 15 inch subs (one active and one passive back to back). I decided to dismantle the old 12 inch sub I built and the horror story there was 4 to 5 dead mice (got in but couldn't get out), anyway took the old sub, reconstructed a new cabinet and wow what a difference. The old 15 inch subs Electrovoice I read only went down to 42hz which explained why I was gettting a lot of sound that shouldn't be in the sub. The 12 Dual voice coil subwoofer from Rat Shack went way lower. I never felt so much deep bass before in my life (well when I auditioned Cerwin Vega Sub). Wow, now I just have to replace the actual 8 inch and 12 inch subs with perhaps SVS subs. 250 watts going into them will definetly rock.