DjBaMBaM, If you are wanting to put these speakers in a car, I would recommend a 2 cubic foot box tuned to 40Hz for each speaker. This is Bazooka's recommended configuration, and for a car, it really is about the best I have been able to model. If however, you want to put these in a house, and you have lots of room, then you might think about one 6th Order box, and one vented box. The reason for the different recommendations for car vs. House is the required Box size. A 6th order box with one sub requires 7 Cubic Feet!!! That's a pretty big box. Too big for a car, (unless you want to remove the back seat.) Even for a home, You might think about using the vented box. To go with both box types you should really use an electronic crossover to seperate the speakers. Besides, most music, (even Rap Music) only goes down to about 35-40 Hz. There is some stuff out there that is used to test your speakers that will go all the way down to 20Hz and there is some classical music (like Organ Music) that will go that low but, it is rare. I think the Vented Box will cover 95% of what you would listen to anyway.
Good Luck