Basically, what I will be using is:

JBL 2370A with PA-D45 compression drivers from 1KHz - ~18KHz
Eminence Alpha 6 on tractrix midrange horn, 300Hz-1KHz
JBL 2226H 60Hz - 300Hz, just as direct radiator, sealed box

The PA-D45's and Alpha 6 is what will be used on the 2way 1KHz Pi Crossover. So obviously this is on the same amplifier.... the 2226H will be on another amplifier though, and if I remember correctly, is 97db too (but who cares, its bi-amped with a large amp :-).

Since the PA-D45's will be 97db with attenuation, I would have to pad the Alpha 6 down 8db as you've suggested.

I am pretty sure I know what you mean by dynamic range, when you say you get an extended dynamic range with the horns though, I dont understand completely.

BTW: Would you reccomend a high pass filter a bit below 300Hz for the Alpha 6 to reduce cone excursion and hence distortion? This of course would be done using an active xover, I can design this myself.

Thanks!
Adrian