# How to measure microphone output impedance

Is there a method to measure the output impedance of a condenser microphone?

Of course. First you must have a repeatable amount of sound. Measure the output amplitude without any load (a high-impedance load, like a o-scope probe, is OK). Next load the output with a resistor equal to your best guess of the output impedance, let's say 1k. Measure the output amplitude again. If it is half the original value your guess was correct. Otherwise solve the equation

B * 1k = A * ( 1k + X )


where

A = open amplitude