I have a 02 Silverado and want to install 2 12's under the rear seat. Right now I have a makeshift box that I tried building and it turned out like crap. My question is does it matter how deep the box is because there isn't much room under the seat for me to build a deep box. Could I still get a good sound if I were to build the box with a bigger width and length rather than height?

 

You need volume in your enclosure. If space is minimal, there are subs out there that will work in smaller enclosures.

 

There's quite a bit of space in a 02 x-cab. We can fit some relatively large subs. But like said, it's best to choose a sub that will work in that type of enclosure. Take a look at our dual 12 box http://www.subthump.com/ctbultra.htm