Box design

HI have tried to design a ported box for 4- 12's. There a 1250 watt RMS speaker. I have built 2 boxes that are garbage. I'm tired of burning them for firewood. Birch is expensive! Is there anyone out here that would help? I would surely appreciate it. ([email protected])

what kinda space you working with

How much air volume did you have with your other builds?

UhHow much air volume did you have with your other builds? 12's need a good amount of air volume to maximize their power & db level. If you do not have the proper amount of air volume their going to sound weak. I have 10 12's & 4 15's in my living room. I have 2 boxes with 2  12's each & their about 44 inches tall & 10 inches deep.