Important hints for the operation of the dynamic cardiod microphones AKG D 12 D 25 D 30 D 40 D 36 D 45 related to output impedance with respect to frequency

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Summary:


Below 300 Hz however the microphone output impedance impedance rises until it becomes twice at 50Hz.


The graph also shows some increase of output impedance at 1KHz.


The paper describes the importance of the amplifier input impedance being greater than the nominal value.