Hi Peter,The 8" JBL cone is what I run from 400-1.8 most of the time. There are some advantages and disadvantages between cones in a horn and compression drivers in a horn. I'm sorry, I'm not an acoustical engineer so I cant help you as far as distortion or probabilities are concerned. .
I have been finding through listening that the cone is a warmer and smoother sound. While the compression driver harder or sharper sound. I like them both to be honest. They are just different. The 8" cone and horn I have found to play out down to 300hz. JBL has rated that driver horn combo to 200hz in some applications but that doesn't work for me. 300 is the limit and i cross is at 400.
I have a virtually flat response out of the 2" compression in the horn from 380-4k. Again, dropping like a rock below 380 I find crossing a 400 too low and I like 500 or a little higher. The compression driver seems to have a little more dynamic or punch to it's sound over the cone. I like it for jazz and voices. The cone is warmer and I like that for orchestral and rock. Rock is just too harsh and I find most of the recording are just bad with respect that they have been EQ'd and mastered to play on low budget systems.
As a final note. I can tell you that this comparison is between a JBL M209-8A, which is one of the best you can find. And a Selenium D405TI compression driver, which is not among the best you can find.
Bill