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12.1.1 MIC connection
The bias for the microphone has to be as clean as possible; the first connection (single ended) is
preferable since the Vmic noise and ground noise are fed into the input as common mode and
then rejected. This sounds strange; usually the connection to use in order to reject the common
mode is the balanced one. In this situation we have to recall that the microphone is a sound to
current transducer, so the resistor is the current to tension transducer, so finally the resistor feeds
the input in balanced way even if the configuration, from a microphone point of view, seems to
be un-balanced.
The following images show some connection examples:
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