'Moving Attenuation Mode' (MAM) enables the AVC value to be set up as a follower. The measured level and a given AV offset value are used for the calculation.

AVC settings: Moving Attenuation Mode

In MAM mode, the 'Release' parameter is not valid and is used as an AV offset value. The release rate corresponds to the 'Attack' parameter, meaning that the release rate is the same as the attack rate.

Averaging time is multiplied by 100 to reach a resolution of 100 ms instead of the standard resolution of 1 ms if MAM is not active. Therefore, the range of averaging time is 1…25.5 seconds.

Calculation of the AVC value: Moving Attenuation Mode

'Skip Calls'

Used to skip the calculation of the AVC value while

announcements are running. The AVC value before the announcement started is frozen and used

while the announcement is active.

'Skip use IO'

This flag is visible if the 'Skip Calls' function is active. Depending on the state of the configured logic control input, the calculation is skipped and the AVC value is frozen while an announcement is running.

'IO Triggered'

Usable if 'IO Triggered' is active and 'Skip Calls' is deselected.

For the 'IO Triggered' setting, the logic control input 1…8 is selected. Otherwise use the fixed analog audio input 4 (IN4) for the AVC microphone.

The meaning and behavior of this flag is changed in the following manner if the 'Skip Calls' flag is active: if priority calls are present, the selected input is used to freeze the calculation of the AVC value.


Assignment of the set value to a local analog audio output. This analog audio output signal will be used for calculation of the AVC algorithm.


AVC takes effect if the noise level at analog audio input 4 (IN4) is above this value.

'Max Attenuation' (Max Att.)

Maximum range of volume control for the AVC algorithm in dB.


Attack rate of the signal in dB/s. A larger value means faster sound level up if the noise level increases.


Release rate of the signal in dB/s. A larger value means faster volume down if the noise level decreases.

'Averaging Time'

Defines the measurement cycle time. A larger number will make the AVC algorithm more stable, but if the interval is too long, the system will need more time to react to noise level changes.

'Feedback Factor'

This value is used for signal feedback of the configured analog audio output. A large feedback factor means that most of the level of the analog audio output is subtracted from the feedback analog audio input level. Therefore, the noise is very loud.

'Show RMS'

Input 1 and 2 level meters display measured RMS values to observe the AVC calculation behavior.