a few newbie questions

ok, right now i have my JL 12w3v2 running in a square box w/ some poly fill (ok a lot of fill, but still)  i was thinking on building a box and doing something like cutting the JL logo into the side and putting a neon in it...............but that woud mean no fill.........

4) i want to go with the slant, that way the box is not so tall, could anyone give me some good measurements to build off of?

thanks in advance

The size of the enclosure determines hwat frequencies you will hear best.  The larger the box, the lower the frequency.  So it all really depends on what you want your sub to hit at.  As far as measurements, it depends on what kind of car, where it is to be placed and how much space you are willing to sacrifice (L, W, H).

A good box should be built out of at least 5/8 inch MDF (medium dendity fiberboard).  Always seal it with a cauking, and line the inside with a sound dampener foam (or equivalent).  The carpet is up to you.