Thanks for all you're help. The crossover diagrams you make are easy to follow. Designing the crossover and "really" understanding it, is something I have difficulty with.

When you get a free moment (I know your very busy) If you could help me with a crossover, I would greatly appreciate it.
Here are the drivers I wish to build into a seven Pi.
All specs are from JBL.

Low frequency;
2226G 4 Ohms sensitivity 89db spl 1/1

Mid frequency;
M209-8 8 Ohms sensitivity 105db spl 1/1 (with horn)
Fs 91hz Re 4.9 Le .265mH Qts 0.385 Qms 2.04 Qes 0.475

High frequency;
2425HS 8 Ohms sensitivity 111db spl 1/1 (with horn)

JBL has recommended in their tuning specs to cross these parts at 420hz, 1.6khz
Attenuating with
+2db woofer
-5db mid
-10db Tweeter
I dont know that this would be the same in a Seven Pi corner horn, but It might be helpful information.

I think this will make a great Seven Pi corner horn.

Thanks,

Bill