Hi,
I've posted a reference to JBLs datasheet regarding the 235x series.
(2)
http://www.jblpro.com/pub/obsolete/23525354.pdf , "Horizontal Off Axis Response"
With the 90°x50° waveguide off axis level exceeds on axis level by several dBs between 3kHz and 10kHz. Second to that level below 3kHz goes down with listening angle as it should with a CD design. This effect comes up with off axis angles as low as 15°.
You don't see the inbalance e/g using this device as intendet from 600Hz up to ~20kHz? Equalization to flat response at some special angle would in any case alter linearity near besides that angle quite a lot. That in consequence gives a definite "sweet spot". Ain't it a contradiction to what "CD" is meant to do?
I wonder why this hasn't been discussed yet regarding home applications of medium to full size CD devices. May be in this respect the older horn/lens 2..3-way combinations do better?!
Juergen