FP+ Series Operation Manual
17
7.4 Audio Input and Output
connections
7.4.1 Balanced Input connections
Figure 7.4.1a: Audio inputs - four-channel
models
Figure 7.4.1a: Audio inputs and loop-thru
connectors - two-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 (-)
Figure 7.4.1c: Balanced XLR wiring schematic
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
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
Figure 7.4.2: Unbalanced XLR wiring schematic
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.
Figure 7.4.3a: Speakon outputs - two-channel
models
Figure 7.4.3b: Speakon outputs - four-channel
models
OPERATION AND PERFORMANCE 7
