I know that the Zobel circuit is to maintain a certain impedance of the load of the speaker at high frequencies. When I test the circuit, the way to measure the impedance is (after measuring the output AC voltage, divide it by the output AC current), but After I came out on the side, whether there is a Zobel circuit or not, the AC current will decrease as the frequency increases. In this way, the impedance will continue to rise, so I don't understand why the Zobel circuit has no function.

Below is my circuit diagram and measure,R9 and L1 are the resistance values of the speakers measured by me.

Below is my circuit diagram and measure,R9 and L1 are the resistance values of the speakers measured by me.