I recently acquired a pair jl 12" subs. One has a surround that is completely ripped all the way through. The other surround is ok but old. I ordered new surrounds thinking I would just redo them both but then it dawned on me that if it was run with the surround ripped, then the motor could have touched the magent and blown the speaker. Is there any way to test the speaker without refoaming it just to find out its blown?
gently push on the cone, does the voicecoil rub? Otherwise take a multimeter and check the ohms rating on each voicecoil. If it's a 12w7 it should be a single 3 ohm if its a 13.5w7 it should be dual 1.5 ohm coils. Idk about the other models though.