I'm building the cabinet to the 8pi. It will look like Wayne's drawing, about 36" by 24", and 16" deep. It will break halfway and narrow to 12" wide at the back. Here is a picture of the upper part from the side - I've sandwiched the horn between the top and a piece of ply the same dimensions as the top and bottom that will support the horn. I had to cut ports in the lower support to open the area behind the Alpha 10 to the cabinet below. The question is will the ports I've cut be large enough? Here is a link to the support. The area of the cutouts total about 115 square inches.