high40s??gee,my truck did a 147.1 playin music on the new meter so,umm yesi know what i am talking about.also,i worked at sound express n tampa where we were at world finals 3 years in a row,and Chris Audio for chris ford,who was a world champion in extreme 1-2,in 93.i have also worked at many local shops near me.so,how many 40 cube boxes for 4 15s have you ever built?? GOT JUGGS????