User guide

CX-A4 INSTALLATION AND OPERATION MANUAL 6
10 VCA Modules
A two-channel VCA module is available as a plug-in option for the CX-A4 (see section 13
for installation details) and is supplied with either one or two control plates. The unit can
operate two channels independently or switched to provide stereo attenuation via one
control plate. For independent operation, the switch should be in the 'solo' position (in),
with the remote level controls connected to both 3 pin connectors. For stereo operation,
position the switch in the link position (out) and connect the level control to the left
connector only. The RL-1 remote control plate is compatible with domestic electrical
accessories and can be mounted onto a standard British flush or surface mounted 25mm
deep back box. Two-core cable with overall screen should be used to connect the remote
level control to the module mounted inside the CX-A4. The circuitry uses the industry
standard 'Thats 2150A' VCA providing very low distortion and up to 90dB attenuation. The
VCA module can be wired to provide muting by using an auxiliary relay connected to a
fire alarm control panel.
Note: A VCA module cannot be installed to channels that already have a stereo EQ
adapter for Bose

equalisation modules installed.
11 Remote Level Plate Connections
REAR VIEW OF CX-A4 AMPLIFIER
1
2
3
USE 2 CORE SCREENED CABLE
CONNECT SCREEN TO TERMINAL 1
REAR VIEW OF LEVEL CONTROL PLATE
LINK
REMOTE LEVEL
CLIP
PROTECT
OFF
ON
SOLO
1
2
1+2
12
SOURCE
12
3
12
3
1
2
15-01-09 V10.0