I couldn't wait, so I threw one woofer in my existing too-small box, sealed, a lot of stuffing, with the H290C on top just to check it out. I was previously using a 4 Pi crossover, so was not difficult to change the circuit to 3 Pi.
As expected, not much bass due to the small, sealed box. I could mount the waveguide in the baffle. However this is just temporary because I will use a ported box to spec.
Have not decided what I will do about the out of roundness.
Attachment:3 Pi test cab.png (Size: 332.36KB, Downloaded 5158 times)