Shure SCM410 - Inhibiting Gating for Unwanted Sounds

Shure Incorporated
21/25
FIGURE 9: GATING BYPASS
Inhibiting Gating for Unwanted Sounds
MaxBus attempts to activate only one microphone per sound source.
Muting a microphone channel prevents its audio from appearing at the mixer's output. However, the muted micro-
phone still communicates with other mic channels via MaxBus. A sound source picked up by a muted microphone
will not activate other microphones.
Sound sources that may cause unwanted microphone channel activation include:
• Heating, ventilation, or air conditioning systems
• A noisy fax machine or printer
• A squeaky door
• A paging system loudspeaker
• An audio teleconferencing return signal loudspeaker
The SCM410 can prevent these and similar sounds from activating microphones as follows:
1. Place one microphone near the unwanted sound source. Connect that microphone's signal to a channel input, -
or- connect the unwanted sound source directly into a channel input.
2. Mute that channel using the logic terminal (see Figure 10). To perform this modification internally on the mixer,
refer to the Shorting Mute In to Logic Ground Internally paragraph in the Internal Modifications Addendum.
3. Adjust the channel gain control just past the level where unwanted sounds do not activate other microphones
in the system. If the channel gain is set too high, the other microphones may not be activated by the desired
sounds. If set too low, unwanted sounds will continue to activate other microphones.