Lowering the crossover point.

[GM]

Thanks GM, I never thought about considering the outside of the box as an issue. I guess my idea of a spherical concrete orb sub is not a great idea?

You're welcome!

This is a whole different 'kettle of fish'! 'Sound is Round', so if sound is radiating around a sphere, there are no eigenmodes in its size pass-band and even these are radiating away at such a steep angle, they dissipate very quickly, so little chance of comb filtering with the driver's output.

The driver of course is flat, relatively speaking, so it will have these strong eigenmodes if some sort of deflection or damping ring isn't used like is seen on some 'FR' drivers.

Harry Olson's early measurements shows how various shapes affect dispersion:

GM

edit: Hmm, looks like the forum rescaled them to uselessness. Do I need to post them elsewhere or did I miss something in uploading them?