Here is what I have to work with.
Sub and port will be firing up.
Port area must be 70 square inches
I'm looking around 5 cubic feet after sub displacement but I have no idea what the displacement would be so we'll say the equivalent of an MT.
I do not have any specs on the sub but I'd like it tuned anywhere between 28hz-35hz.
I have tried to design this myself but I'm not sure what to do about port area and all that. Oh and the sub is the 15" Nightshade Prototype. Thanks for the help.