Why three ports?? What kind of extrusion does the speaker have? Is that why there are so many ports? Is the box really plywood? Seems like awfully resonant cabinet. Think I would really make an effort to isolate the frame of the speaker from the box. Got a picture with the driver in it?

__________________
On some nights I still believe that a car with the fuel gauge on empty can run about fifty more miles if you have the right music very loud on the radio. - HST

1983 300SD - 305000
1984 Toyota Landcruiser - 190000
1994 GMC Jimmy - 203000

https://media.giphy.com/media/X3nnss8PAj5aU/giphy.gif