Newbie crossover impedance question

[Xylenz]

There's one thing that I have never understood about crossovers (ok there's lots of things but this is a big one). Forgive my naivete but I have to ask it.

If I have an N ohm woofer crossed over to an M ohm tweeter what is the impedance of the entire speaker as a system? I'm assuming that it must depend on the type of crossover but I dont know. How do you predictively calculate this?

 

[f4ier]

Try Speaker Workshop, Crossover Simulator and JeffB's PCDC which you can download from the FRD Group's site. Work with measured impedance curves rather than calculated curves.

 

[planet10]

If I have an N ohm woofer crossed over to an M ohm tweeter what is the impedance of the entire speaker as a system?

The nominal impedance of a speaker is just that, nominal. In a situation like this the nominal impedance would probably be N ohms.

The actual impedance -- assumming a well behaved XO -- is a spiral in a 3-space with axes frequency, magnitude, & phase.

dave