I'm looking at my 2226's and thinking about mounting them flush, and I see two potential problems. First, the driver has a thick gasket that is rather firmly attached. Second, the gasket somewhat covers the holes for the mounting screws, and the holes are flush against the side of the driver frame, i.e. there is no clearance for the head of a screw. (I have bought some t-nuts and pretty stainless steel screws to use for mounting.) It appears that this driver is meant to be mounted internally.
The gasket sits proud of the frame and is attached to the cone which is attached to the frame. It looks like it should not be removed, for fear of damaging the cone. (The screw issue is relatively minor.)
First of all, are there any comments on the above? And second, are the wave-lengths involved ( up to 350Hz at the most - more likely 200 since I am building a mid-horn, too) so great that how the thing is mounted is largely irrelevant with regard to edge diffraction? Finally, if it is mounted flush, does a gasket need to sit between the frame and the box? If so, do I need to remove the gasket from the front and use it, and is that feasible?
This question should be pretty clear if you have a 2226 to look at.