is there any differance in sq or spl if u mount a sub out side the box vs mounted normal. going to build a box for a xcon 18 and is it doesnt really affect it id like to show off the basket and magnet . any help would be appreciated

no not really, you will have to wire it out of phase also you will not need to subtract the displacement of the woofer from the net volume of the enclosure.

by out of phase do u mean switching + and - around

by out of phase do u mean switching + and - around

Exactly

thanks and any one with with experience with the 18 xcon are the optimal box plans for sale on here in the ball park

thanks and any one with with experience with the 18 xcon are the optimal box plans for sale on here in the ball park

SSA has a couple free enclosure designs: link

If one of those don't work for your vehicle then you can get one through the ssa store.

The designs are made / approved by SSA after all, so yes they would be optimal

You don't have to wire it out of phase, wire it how it sounds best.

You could also experience some mechanical noise from the moving parts as they wont be masked from being in the enclosure.