“Wedge” Shaped Box - Port Extension Question (SUV Rear Firing)

I’m designing the sub box for my 2013 4Runner for three W12GTi’s. It will be a fairly simple “Wedge” behind the 2nd row seats. The angled “Wedge” will obviously mate up to the back of the rear seats (no speakers on the wedged front), and the Subs and Port will be rear-firing on the 90 degree “back” of the box.

The port will be on one side on the back baffle (3 subs offset to the left with a vertically oriented rectangular port on the right side as viewed from the rear hatch), and will use the side of the box for one of its port walls.

The question: If I extend (bend) the port from the side wall to the angled wedge front, how should I estimate the length? Will this present any other issues with the odd angle where the perpendicular port meets the angled wedge front?

If the “front” of the box was square, the port would obviously just bend around the 90 degree corner – but since the “front” is angled (the wedge), it won’t be a simple 90 degree bend from the side of the box. I guess it’s vaguely similar to having the vertical port on the wedge baffle and then trying to extend it to the “square” back, but the inside bend is obviously different…

I still plan on keeping the extended port wall parallel to the angled front wall and keeping the inside-end of the port perpendicular unless there is a better way to terminate the port inside the box considering the odd bend angle. (Such as having the top part of the inside end of the port end up longer than the bottom to compensate for the odd bend where the port is longer on the bottom span).

Sorry for the poor quality of my MS-Paint "artwork" – I’m still figuring out Google Sketchup :)



Thanks for any tips!

Randy V.