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Detector - Adjustable Detector Control
Detector. The MR88 gives comprehensive control over channel detection.
Channels are connected to the output, dependant on priority setting, when a
signal is detected. The method used for detection can be selected by type of
input. These are Auto Speech, Auto Music, Manual Level Set, Detector
Forced On, and Detector Forced Off.
Auto Speech detector is an adaptive threshold and is very useful in noisy
environments, as the microphone will only trigger 6dB above the background
noise.
Auto Music Detector is designed to detect music.
Manual Detector Level setting can be set so that the channel triggers on a
specific level of sound (-40dB to - 0dB).
Detector Forced On is used to make the selected channel appear triggered
even when no sound is present. This can be useful for setting a particular
microphone to be the ambient microphone of a system rather that use the
“last one on” function, or used in conjunction with external control as a
manual mixer.
Detector Forced Off is used to make the selected channel never trigger on
sound. It can be used in conjunction with external control as a manual mixer.
Hold - Time
Hold time is the time a microphone channel is below trigger level before it
releases the lockout bus. The Hold time is adjustable with 5 settings.
50mS, 200mS, 500mS, 1 Second, 2 Seconds. The fastest setting will allow
microphones to switch on the slightest break in the speech. Sometimes it is
desirable to extend this time. E.g. Voice over music applications might need
the longest hold period.
NOMA (Number of Open Microphones Attenuated) Control
The NOMA system helps reduce feedback, by allowing for the increase in
system gain, as the number of open microphones increases. When selected,
the MR88 identifies exactly how many NOMA selected microphones are on,
and automatically adjusts the gain. However, NOMA will reduce the sound
level of each individual person speaking, which may not be desired,
especially in applications such as conferencing. By selecting this function
individually for each channel the system designer can control which
microphones are included in the NOMA calculation.