I am building an enclosure this afternoon for a friend, but I do not design them,, just build them. most of the time people have an idea and we will build from there. this time i need your help. the size of the enclosure need to be
13 1/2" high
14" wide (deep)
24" long

tuning ar 30 HZ

build the box is easy, i just do not know how to design the port.
thanks for any help will be for a 12" sub