10-15-2003, 07:21 AM
I am building a ported box for 2-JL12W0-8's. I am making them in a common chamber box with no seperation. In the specs it says to double the ports or add them up if making a single port. Here comes the question which may not make sense. When using a speaker box program. Lets say one of the speakers require a 2.5 cubic foot of space. You double it to 5.0 cubes. The port for a single woofer in a 2.5 cubic foot box is 4" by 12" which came to a tuning of 31 hertz. Now if you double the ports up, it comes to a single port measuring 8" x 12'', you will no longer have the box, which is 5 cubic foot, tuned to 31 hertz. When using the speaker box program and you tune a 5 cubic foot box with the 8" x 12" port it comes to around 39 hertz. Does this make any sense to anyon? So would you tune the box as if it was a single 5.0 cubic foot box which, when using the program, would come out to a 6" x 11.5" port at 31 hertz. I am using the WinISD program. I also tried other programs and came to the same conclusion.