I wired by dual coil subwoofers the other week successsfully but I may have made an error in the wiring. I wired them at two ohm in series so they should look like the first below.
The problem is that I may have accidentally wired them like the picture below. What Ohm is this and if its something made up, what can this damage? The subs sound is fine but I think the volume should be louder. The only difference is that the + (red) to - (black) wire is on one side opposed to going to the other side of the woofer.