Ι know how to measure fr, the impedance is that i want to... can you tell me how ? i dont use external soundcard(i have usb mic for the fr. )
As i can see in the drawing i must put a sense resistor the same value that the panel displays first of all, but i dont have separate sound card so how would that be?
Just on series in one channel to the one of the binding posts (+ or - ) and the other where ?
Your PC needs to have a headphone output and a stereo line input to make an impedance measurement. Connect up as shown in the diagram in the help. The sense resistor is in series from the right output channel to the speaker + terminal. The speaker - terminal needs to connect to the ground of the PC's input connection.