QSC Audio CX Series - Manual (Page 7)

6
Channel 2+
Channel 2-
Ground
Ground
Ground
Channel 1-
Channel 1+
Loosen screw,
insert wire here,
then tighten screw.
III. Inputs
CX amplifiers feature balanced inputs, connected via a Euro-style 7-terminal
detachable header. Attach input signal wires as shown. If you are connecting an
unbalanced signal to an input, use the non-inverting (+) input and the ground
terminals of the header, and also connect a wire jumper between the inverting (-)
input and the ground terminal. The wire jumper will prevent a reduction in gain
caused by a floating input.
If you need XLR or 1/4” RTS inputs on your CX6, CX6T, CX12, CX12T, use the optional MX-1
input expander (available through QSC’s Technical Services Department).
Typical of QSC amplifiers, the input impedance of a CX Series amplifier is 20 kilohms balanced
and 10 kilohms unbalanced.
Each CX Series (except CX4, CX4T) amplifier features a Level I Open Input Architecture slot.
See the Operation Chapter for more information about Open Input Architecture.
INPUT SENSITIVITIES
Audio signals of these levels will produce full rated output power at 8 ohms.
CX4, CX4T 0.98 volt (+2.0 dBu)
CX6, CX6T 1.02 volt (+2.4 dBu)
CX12, CX12T 1.00 volt (+2.2 dBu)
IV. Outputs
Covered barrier strips located on the rear panel allow speaker cable connections to the amplifier
outputs. See the diagrams for details on connecting speakers and/or distributed (25-, 70-, or 100-
volt) lines. For attaching wires, we recommend using insulated connectors of the type shown. Always
make sure the amplifier is turned off before you change any output connections or lift the safety
shroud.
If you are operating the amplifier in bridged mono mode to achieve higher output voltages, neither
speaker wire is grounded. Therefore, use the same precautions in handling and dressing the wire
that you would for the normal “hot” outputs. See the section on bridged mono operation for
additional important instructions.
If you are driving a distributed line, make sure the sum of all the power demands of the speakers
does not exceed the amplifier’s power rating. In fact, it is good practice to allow about a 25% safety
margin. For example, if the load on the distributed line is 400 watts, use an amplifier with a power
rating of 500 watts. See the Application Notes in the back of this manual for more details on distributed lines.
Lift safety shroud.
Loosen screw
terminals.
Insert wire connectors
under screws.
Tighten screw
terminals.
Lower safety shroud.
Balanced input
connections
Shield
Signal conductor
Wire jumper
between
input and
ground
Unbalanced input
connections