I'm just starting my journey into using horn speakers. I've got a pair of Altec 288-16K CD's and Altec 416-8B woofers that I'm building a speaker pair from.

Thanks to Wayne, I've been learning a lot about crossovers lately (Crossover 101 thread) and investigating his Pi passive crossovers. I haven't got all the math figured out just yet and wondered if anyone can help me understand how to tweak component values if one driver is at a higher impedance than another (e.g. my 16 ohm CD and 8 ohm woofer).

Do I just parallel a 16 ohm resistor across the compression driver input for an 8 ohm load to match the woofer? Coversely, I guess I could run an 8 ohm resistor in series with the input of the woofer to bring it up to the same level impedance as the CD (depending on what impedance I need for the crossover circuit to work). Would either of these work? Is there a better way to do this? Am I asking for trouble in using drivers with dissimilar impedance?

Finally, what impedance value do the Pi crossovers assume for their respective drivers?

Thanks for any help,

Erik

Yes, you could add a resistor to either driver to make the Z's the same, but a series R to the woofer will KILL your amplifier damping ability and throw away 1/2 the LF energy as HEAT, while a shunt resistor will merely drop the HF driver by 3dB while blowing off 1/2 the HF energy. INEFFICIENT as hell. And a waste of good components. You can always rework the HF crossover values for the 16 ohm HF Z, why exactly is THAT such a forbidding prospect in the first place? Sam