You are correct, I did miss the point. I think at this point I am just going to buy passive crossovers based on the info provided by the driver manufacturer, which seems to be the simplest solution.
Thanks for the input..
Without measurement equipment and other tools, not to mention know-how, this is probably the best option. And I hope you're referring to a schematic from the manufacturer of the coaxial driver.
I will add to this that filters based on a text book "8 ohm load" are really only useful for designing active crossovers and for general discussion of crossovers. The real impedance curve of a typical driver is anything but "8 ohms". A compression driver in particular will have significant ups and downs near the crossover region which means that the resulting filter curve, and sometimes more importantly, the resulting impedance curve are rather complex. Unless you're going into very sophisticated crossovers with zobel networks etc, or you're lucky, you're not going to be able to best the response of even an economy speaker today with a generic crossover. Nor with a crossover intended for different drivers/horn/system.
