
A priority mixer control for a multi-microphone audio system comprises a threshold signal generator that develops a scanning D.C. threshold signal starting at a maximum level for a time T1 and then decreasing in amplitude as a function of time. Each microphone channel is provided with a control channel including a comparator that compares the microphone signal, as an A.C. signal, with the threshold signal, and that switches the microphone channel to "on" condition when the microphone signal exce...











