Separate Chambers or One Big Open Box?

i am looking into building a box for my friend and the question arose if we should have separate chambers or one big open box. i have heard many things when it comes to this about how you should never have a box without separate chambers, but there are so many boxes like this.  to help me out i am looking for the difference in sound quality, spl anything to that effect and i want to here your arguments for or against certain boxes and why....thank you

bobby

My opinion is you should always use seperate enclosure spaces, as it is actually simpler to calculate the proper geometry and easier to make adjustments if it doesn't come out just right.  Also, there is less chance for cancellations from one speaker interfering with the other.  In general for SQ, seperate enclosure spaces is critical.  For SPL applications it doesn't matter nearly as much unless you get the ports wrong, then it can become a big pain to fix the problem.

In general if you want to share airspace for two woofers, you need to make sure the two are as closely matched to each other physically and electrically as possible.  You need to make sure they are both driven from the same amp (preferably a mono amp.)  You need to be very careful with your enclosure construction for size and ports, and I suggest you use 1" MDF for the front baffle (where the woofers are mounted) and that you over-brace internally.