The control panel of the Gated Automatic Microphone Mixer provides control and monitoring for the AMM’s inputs and output as well as control of the way the AMM’s gates perform.
The Input Meter on each channel displays the level of each channel’s incoming audio signal.
The AutoGain Meter on each channel displays the amount of gain reduction being applied to the channel. This includes gain reduction due to gating, ducking, and NOM attenuation.
The Priority setting of each channel allows a channel or group of channels to override other channels. Priority 1 is the highest Priority setting and will override any channels with other Priority settings. For example, this allows a chairperson’s microphone to always be heard above any other microphone in the Gated AMM.
The Gain Control is equivalent to the fader on a traditional mixer and may be used to adjust the volume of individual microphones while using the Gated AMM.
Engaging the Mute button will mute the channel’s signal to both the mix and direct outputs of the Gated AMM.
If multiple channels are placed in the same Mute Group, muting or unmuting any channel in that group will control every channel in that group.
The threshold control allows the channel’s gate to open when the input signal reaches a predetermined signal level. The manual threshold setting is only used if the Auto Threshold button is turned off. If Auto Threshold is on, the Gated AMM will automatically calculate a threshold level for each channel based on the signal levels of all other channels or based on the ambient microphone input.
Engaging the Bypass button will allow the channel’s signal to pass through the Gated AMM without being modified by the gating algorithm. Channel controls such as Mute and Gain will still affect the signal.
If the direct outputs are enabled, the signal sent to the direct outputs will always be post-gate. The direct output control allows this signal to be selected between pre-NOM attenuation or post-NOM attenuation. In most cases, post-NOM attenuation will be appropriate.
The Output Section provides a meter, gain control, and mute for the Gated AMM’s main output. These controls will have no effect on the direct outputs of the Gated AMM.
NOM Attenuation provides a 3 dB reduction in gain to each active channel for every doubling of the number of active channels. This means that if two channels are simultaneously active, each channel will be reduced by 3 dB. If a third channel becomes active, each channel’s NOM attenuation becomes,
-4.7 dB. Four active channels cause a 6 dB reduction, etc. This reduction in gain, based on the number of currently active channels, helps to ensure that the overall system gain remains stable regardless of the number of currently active channels.
The NOM Limit control determines the maximum number of channels that can be active at one time. When setting the NOM limit, it is important to remember that channels are held open for a period of time after the talker has stopped speaking. Setting the NOM limit too low can create a situation in which channel gates are unable to open while waiting for previously used channels to close.
Designated Mic On
It can be beneficial to ensure that the gate for at least one microphone channel is always open. If the gates for all channels close, teleconference far-end participants may perceive the complete silence as the call being dropped. The Designated Mic On control allows a selected channel to be automatically opened if no other channels are currently in use. Alternately, the Last Mic On setting allows the Gated AMM to simply hold open whichever channel was last used.
The Link control is used when linking multiple Gated AMMs to function as a single device. When manually linking multiple Gated AMMs, one AMM is set as the Master and all others are set as Slave devices.
The advanced control section is normally collapsed and may be expanded by clicking on the expand button on the lower left corner of the control panel. The advanced control section provides access to individual gate settings for each channel as well as the Automatic Threshold setting controls. These controls may be used to tailor the response of the Gated AMM for unusual or difficult installations.