Well, if you have the space, then go with the 10". Most often 2 8's = 1 10". Unless it is a super 8 like Digital Designs or W7.
make sure the sub will work with that amp at 2ohms to get the full 400w. Why are you going with JL? Have you looked at Elemental Designs, Assendant audio, Image Dynamics, CDT, etc? They may give the same or in most cases better performance than the JL at a greatly lesser cost.
make sure the sub will work with that amp at 2ohms to get the full 400w. Why are you going with JL? Have you looked at Elemental Designs, Assendant audio, Image Dynamics, CDT, etc? They may give the same or in most cases better performance than the JL at a greatly lesser cost.