In Reply to: A question about speaker impedence ratings posted by wunhuanglo on July 10, 2003 at 01:04:46:
Advertised impedance is a sort of an averaged value. The impedance rating of loudspeakers is an approximate value, and is what you can usually expect in the midband of each subsystem. The crossover prevents each driver from loading the system except in its passband, so the system impedance curve looks much like the individual impedance curves of each of its drivers, connected by a transition region between each. To know overall system impedance as a function of frequency, you can either measure at several frequency points or you can model the loudspeaker circuit with Spice.
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