PURPOSE: To obtain a cut-off characteristic crossover of 60dB/decade, by driving speakers sharing high and low bands adjacent in a multi-wax speaker system, via a specific electric circuit according to the characteristics of each speaker.

CONSTITUTION: A high frequency resonance frequency of the minimum order is suppressed to a woofer 1 with an inductor 5, equivalent resistor 6 and capacitor 7. The impedance viewing right from a bondary 24 is made to a constant resistance by a capacitor 8, equivalent resistor 9 and inductor 10. The minimum resonance frequency of a tweeter 2 is suppressed by a capacitor 15, equivalent resistor 16 and inductor 17. The impedance viewing right from the boundary 26 is made to a constant resistor with an inductor 18, equievalent resistor 19 and capacitor 20. Thus, a speaker drive circuit with the cut-off characteristics of 60dB/decade for the crossover characteristics can be achieved.