impedance measuring

[Multi-Volti Devices]

I like the more sophisticated approaches suggested - because the results are
safely interpreted...once you understand the test setup

The series resistor adjusted for half voltage method give you the Thevenin
equivalent impedance magnitude (basically it's the polar form impedance
ignoring the phase....by this I mean the impedance represented by a real +
an imaginary component (resistance +j(reactance), converted to polar form =
this magnitude at a certain phase angle you don't need to know for the scope
of your question).

I would think you could do something similar if you had a signal generator
that could drive a speaker (hey, your rig with the xtal calibrator tuned
in?) and then measure the output voltage across the microphone and the
series resistor with a scope.

An impedance analyzer does something similar with an amplitude reference -
you don't need to have equal voltages - voltage divider rule allows
calculation of impedance magnitude.

The other Murray

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