The Gallo stuff looks neat. I read the reviews and started looking around for spheres.I found hard hats.Light,rigid,but kind of a tight fit for 6x9s. 2 layers of MDF at the opening could give me about 7" of depth,which is close to what some of the commercial enclosures have.The opening is not flat,but I'm sure that can be accomodated.If I had MDF on hand I'd be starting now.I know nothing about proper enclosure sizing,and I don't know if car speakers have published T-S parameters,which I think is where one starts,if one has a clue.For myself,I'm a beginner,but I'm willing to take a shot.
J