Jim said:
You need to be shooting for a crossover in the low 2000's Hz(possible) or sub 2000 which the PT2 can not do. I have used the PT2 type planar as low as 2300 Hz (third order).cmanning,
The higher the order of the filter is the lower you'll be able to cross. If Jim used a 3rd order at 2300Hz. You could certainly drop it to 2000Hz with a 4th order slope. Probably even lower if you wanted too.