Unlike traditional alignments, horns don't rely so heavily on XMAX. Infact, using high XMAX drivers in a horn will lead to "throat overload". The pressure inside the horn path gets to a point where a negative pressure wave creates a vacuum effect causing turbulence and compression within the horn ultimately resulting in distortion.
The original Adire Tempest (Manufactured by Eminence) was a popular horn driver. How close are the original's t/s to the new Tempest-X?
True, at frequencies where the horn is really "in effect." However, these guys are talking about wanting the high-xmax drivers specifically for lower frequencies, when the loading at the throat is decreasing...
Both good explanations. I'm still learning about horns so any bit can help for me. I know there are tons of people out there who have good knowledge of sealed, ported, or bandpass enclosures but no experience with horns (I'm one of them but one step at a time right!!). Still waiting on our shipment of the prototypes but will update when we get them with some nice pics and assembly thoughts.