Audio Input And Output Connections; Balanced Input Connections; Unbalanced Input Connection; Speakon Output Connections - Lab.gruppen FP+ Series Operation Manual

7.4 Audio Input and Output
connections

7.4.1 Balanced Input connections

Audio inputs and loop-thru connectors - 2-channel
models
Audio inputs - 4-channel models
The XLR input connectors are electronically ba-
lanced, and wired according to the IEC 268 standard
(pin 2 = hot). XLR input connectors should be wired
as follows:
Pin 1 Ground/shield
Pin 2 Hot (+)
Pin 3 Cold (-)
When linking the same source signal to
several input channels, be aware that there
is a limit to the number of channels an
output source can "drive". A typical output
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source (e.g. a DSP crossover unit) can drive up to
four amplifier channels before external line-drivers
might be required to buffer the signal.
7.4.2 unbalanced Input connections
To connect an input to an unbalanced source, it is
possible to connect pins 1 and 3 in the XLR plug at
the amplifier end of the cable. However, a better
method is to connect pin 3 to the shield at the source
end of the cable, as this usually results in better hum
and noise rejection. Balanced input connections are
recommended whenever possible.

7.4.3 Speakon Output connections

Refer to the instructions in this section if your amplifier
is equipped with the Speakon output connectors.
Speakon outputs - 2 channel models
Speakon outputs - 4-channel models
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