Microphone Gain; Vox Sensitivity Level; Vox Delay Time - Albrecht AE 6491 NRC Manual

7.1.1. Microphone Gain

Set the level of the microphone gain in VOX mode. The bigger
the distance between the speaker and the microphone, the
higher the value must be selected. With an higher value, noises
such as e.g. wind and engine noise will be transmitted.
You can set the delay time in 9 levels.
The default setting is level 6.

7.1.2. VOX Sensitivity Level

The VOX level sets the noise level at which the automatic VOX
transmission is activated.
1 = low sensitivity, VOX only reacts to very loud noise
9 = high sensitivity, VOX already reacts to very low noise
The default setting is level 6.

7.1.3. VOX Delay Time

The VOX delay time determines the time after which the
automatic VOX transmission turns off without any sound being
detected:
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