JBL LSR4312SP, Owner'S Manual

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Appendix E: Wiring Requirements
Analog Connections
For optimum performance, some attention to wiring details now can reduce system degradation later. The
cabling recommendations given below follow standard wiring practice for differential inputs.
Balanced Sources
The best way to run your system is balanced, where both “HOT” (+) and “COLD” (-) signals are supplied
from the source along with a GROUND/SHIELD. These are typically carried on two conductor shielded
cables with XLR connectors on both ends.
Alternatively, connectors with Tip, Ring and Sleeve (T/R/S) jacks can be used. Whenever possible, the
cable shield should not be connected to any signal pin, but left to perform a cable shielding function only.
X
Under no circumstances should the safety ground wire be removed from the AC power connector.
When using balanced sources with the LSR4312SP, either the XLR or T/R/S input connector can be used,
since the circuit is common to both.
For balanced signals, the HOT (+) signal from your source should be connected to the tip of the T/R/S
connector or Pin 2 of the XLR input as shown in Diagram A. The “COLD” (-) signal should be connected
to Pin 3 of the XLR or the “Ring” of the T/R/S connector. To avoid ground loops, connect the SHIELD at
the source end but not at the LSR input.
Unbalanced Sources
When using unbalanced sources, there are more possibilities to introduce ground loops into a system.
The LSR4312SP offer several ways to help alleviate potential problems with unbalanced equipment.