My new sub/amp install

[talnlnky]

if there are two cones, that doesn't make it Dual Voice coil... Most likely what you have is one of the following...
1: Two subs in an isobaric chamber which means the way they are wired allows them to work in a MUCH smaller box than normal.
2: Passive radiator.... it's how you get a ported box, in the size of a large sealed box. You add basically a sub... withouth voice coils... it just sits and moves to the music/pressure and makes the sub perform as if it were in a ported box.