Sloped baffle

Certainly, but a lot of other problems would be fixed.

Roy. thanks again. ^ Wouldn't using 2nd order cross-overs compromise the whole effort?

I just remembered the name of the old poster that started a time coherent speaker company; Karl Shuemann. To be fair to all here's a list of those companies that have made time coherent speakers that I'm aware; of starting with Karl's (which fortuitously falls into alphabetical order):
Audiomachina
Dunlavy
Greenmountain
Meadowlark
Quad
Thiel
Vandersteen

^oops!
I forgot the original Ohms with genuine Walsh drivers
and perhaps their progeny from HHR-ExoticSpeakers, German Physiks and Huff might qualify too.

Unsound, are all of the companies listed in your last post still making time coherent speakers. Of course, Vandersteen, Thiel and GMA are obvious. Not sure about the others.

Btw, been in contact with DEQX. Will try and arrange a home demo. If I can pull it off, I'll report back.