Originally Posted by
davef
With a vertically oriented horizon with the ribbon tweeter rotated, because the tweeter and midrange would now be aligned horizontally, symmetrical horizontal dispersion (to the left of the speaker and to the right of the speaker) is slightly compromised. However, the horizontal dispersion is so wide regardless, I don't think any compromises would be audible. Keep in mind this is exactly what we do with our HTM-200's, and customers love the way the sound and image.
Sometimes not having symmetrical horizontal dispersion, if done right, can be beneficial as you end up getting less issues with reflections from side walls. This was done purposely in the design of the M&K S-100 and S-150.
340's are a different beat entirely and the EXBAC crossover optimizations are more for compensating from the extended baffle created when a speaker with such a small front baffle is placed in or on an entertainment center.