How do you build a good sub box?

I need help on knowing how to build a sub box that will hold 2 15" Diamond Audio CM3's. The air space needed is 1.2-2.0 square feet for an enclosed box. I just dont know were to start or what I need to do so any information will help. And yall are probly getting tired of hearing from because it seems like I just wont leave yall alone but I dont know anyone that can help me besides yall so thanks for everything.

Its good to ask questions.

As for the enclosure you will need a design, there are several ways to get that either find someone online, or there are a few online designers, all you need is the amount of space you have. Next you should use 3/4"MDF which i about 20 a sheet, and a box of drywall screws, ive seen people use other things but drywall screws seem to do pretty well. You need wood working tools, table saw, circular saw, drill, jig-saw or whatever its called. Measure everything out on the sheet and double check that to make sure it will work right, cut all the pieces and get some extra hands for a dry fit, no screws or anything just to make sure everything lines up and is correct. I should have my new 15" enclosure tomorrow, 6.5 cubes for 2-15"s ported to 28 hz. Il post some pics up and remember yours will only have 6 sides, mine will to but i have the port as well.

ok ya tell me when you get pics up id like to see it. This is exactly what I need but just custom built by me http://caraudiofactory.com/20012007-chevy-avalanche-poly-or212-or210-p-231.html. And do I need to use that selant stuff on the edges of the box? And when I get it coated with bedliner should I coat the inside of the box too?

you put the sealant along all of the inside edges of the box where two pieces of wood come together. bedliner won't hurt on the inside, will just make it a little stiffer (which is good).

O.K. and I had one more question how would 1 15" compare to a 10". I heard one 15" is equal in volume to 2 10", then some one argued that and said it was equal to 3 10". And you are probly going to say its all in box instalation but I mean if the boxes were exactly the same.

There both idiots. Ive heard 10" subs that can get as loud as a single 15". There are a lot of variables in how a sub sounds and reacts. Amp, type of sub, enclosure, and vehicle type. But generally speakeing if you want a lot of bass, then more displacement of air will net a louder setup. But just saying that any 15 is as loud as 2-10"s is stupid.

the general rule of thumb is 2 subs is roughly equal to 1 sub o the next size. so 2 10's = 1 12, 2 12's = 1 15. This is nowhere near exact, just a guideline. Of course, as stated, the car, box type, box location, amp power, etc .. will make a huge difference. Much of it is also with what you are trying to accomplish, max SPL at like 40-50 Hz is MUCH easier than loud, low bass (below say 28 Hz).

Alright thanks ill just let them read this because I told them it was all in the installation. But just cuz I was younger they thought I was wrong