10/29/2019
Tech Works CI-Series Systems Planning & Installation Manual Page
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Automatic Level Control, ALC:
To allow collaboration, all the users need to have similar Audio Levels
Even though the signal sources may vary in input level
The CI-BUSS products process the Audio Sources using Automatic Level Control, ALC
Each Input is adjusted to be approximately 6 dB into limiting, ~ twice the system level
So the user may talk louder, of if the signal is diminished, the output is not affected
The ALC is associated with the Microphone Gain (Reach) Control (16 Position Rotary Switch)
A Setup Indicator, Off, if source is muted,
Green
when the Source is keyed, Flashing
Red
when
limiting
AU
DI
O
IN
PU
T
LE
VE
L
VCA AUDIO OUTPUT LEVEL
Threshold of Limiting
LED Flashes
Red
Setup:
The Microphone Gain Control is increased by ~3dB/Step
While an input is present, the Control is advanced CW until the “Threshold of Limiting”
This establishes the “Normal Input Level”
Advancing the Microphone Gain CW, increases the gai
n…
however the Output level remains the
same
For most Applications, two clicks, or ~6db of extra Gain is sufficient
Excessive Gain is not recommended:
The background noise level is increased
The susceptibility to Feedback is increased
