EN
9
Gain Controls
The Gain controls are recessed and can be adjusted 
with a small screwdriver or flat tool. If desired, the Gain 
Control Security Cover can be installed to prevent 
changes to the installer's settings.
Turn the gain controls clockwise to increase gain and 
counter clockwise to decrease gain. The maximum volt-
age gain of the amplifier varies depending on the model 
designation. Maximum voltage gain for each model is 
shown on the front panel label in parentheses adjacent 
the 0dB attenuation setting.
The Gain controls are marked in dB of attenuation. 
There are 21 detents for repeatable adjustments. The 
upper 14 steps are about 1 dB each, and settings 
should normally be made within this range. The range 
below -14 dB should not be used for normal program 
levels, as the input headroom could be exceeded, but 
can be used for testing at reduced levels. At the mini-
mum setting, the signal is completely cut off. 
Gain Control Security Plate
The cover blocks access to the Gain settings. The LED 
indicators are still visible to monitor the system's opera-
tion. 
1. Use a 9/64" or 3.5 mm hex driver to loosen the screw 
several turns. Do not remove it completely.
2. Slide the right end of the cover under the loosened 
screw.
3. Insert the left end tabs into the last row of ventilation 
slots, and slide the panel fully to the right. It should lock 
into the slots.
4. Confirm that the LED's are visible through the cover. 
Tighten the hex screw carefully. 
Gain controls on 2-channel models. Mark-
ings will vary depending on model.
Gain controls on 4-channel models. Mark-
ings will vary depending on model.
CX902 shown with gain control security plate installed.