QSC CMXa Série Mode D'emploi page 14

Connections
Inputs
Each channel has active balanced XLR and ¼" (6.3 mm) inputs wired in
parallel (— Figure 25). The input impedance is 20 k balanced, 10 k
unbalanced.
Balanced signals are less prone to AC hum, but unbalanced signals can be
suitable for short cable runs. The signal source's output impedance should
be less than 600 to avoid high frequency loss in long cables.
Balanced Inputs
Use the XLR or ¼" (6.3 mm) TRS input jacks, or the barrier strip
26 through — Figure 28).
Unbalanced Inputs
EN • Connect the unused side (Pin 3) of the balanced input to ground (Pin 1), as shown in
• A tip-sleeve ¼" (6.3 mm) connector will correctly terminate the unused side of the input as shown in
• For Stereo operation, use the inputs for both Channel 1 and Channel 2. For Parallel or Bridge Mono operation, use the Channel 1 input.
• See the section on operating modes for more information. To patch the audio signal to other amps (Parallel and Bridge Mono modes only), see
the instructions for using Parallel Inputs on
XLR unbalanced Jumper pin 1 to pin 3
page 9.
1 =
2 = +
3 =
— Figure 26 —
Balanced Unbalanced
(— Figure
— Figure
TRS unbalanced
No modifi cation needed
— Figure 27 —
— Figure 28 —
14
— Figure 25 —
26.
— Figure 27.