Sando, you are a hoot!
I agree there is soooommme small resemblance to a birdhouse, but if they sound as good as I suspect, I wouldn't mind if they looked like an outhouse! I suspect the shape is not purely asthetics and has some functional benefits related to refraction. That tweet sure is sweet and the Excel is one of the best mids on the planet. I bet it sounds pretty darn good.
J
PS: I was going to call it: "what happens when you cross an 1801 with a Criterion..."