a dual 4ohm sub can be wired to 8ohms or 2 ohms unless i'm missing something it can't be wired to 4ohms. so that sub is most likely wired to 2 ohms allready.
Well its a Dual 4 ohm sub that you are referring to. Two seperate 4 ohm voice coils... Can get tricky. I have 2 Dual 2 ohm subs... wired together on one amp allows me to run 2 ohms.. If I ever decide to fix my other JBL 1200.1, then I will be able to run a 1 - 12 on each 1200.1 at 1 ohm. Wont ever do it though, unless for competition, because you know.. I want to keep my subs.