ever think about JL subs? I have 2 JL W3 12's and a JBL 600.1 mono amp can be extremely loud if volume is turned up but sound quality is really good when not competeing in SPL. The JBL amp is an older amp prolly about 3 years old or so but i think you can still find them around. 143.3 DB in my civic and 148.4Db in my previous Blazer