4
XPA U Full Rack Series Audio Power Amplifiers • Setup Guide (Continued)
6 Output Mode Selection Switch (see figure 3 on page 3)
This switch determines the function of each amplier channel. There are six settings: two low-impedance
(8 ohms, 4 ohms) and four high-impedance modes.
Low-Impedance Modes (8 ohm/4 ohm):
The 8 ohm stereo setting is used when connecting to 8 ohm speaker loads, and the 4 ohm setting is used
when connecting to 4 ohm loads.
High-Impedance Modes:
• There are four high-impedance modes available: 70V, 70V (HPF OFF), 100V, 100V (HPF OFF). These modes are used
when connecting to distributed 70 volt or 100 volt loudspeaker systems.
• In the 70V and 100V modes, an 80Hz, 12 dB/octave high-pass lter is applied to the signal, to prevent saturation of the
transformer cores in the speakers.
• In the 70V (HPF OFF) and 100V (HPF OFF) modes, the high-pass lter is disabled. The (HPF OFF) modes should only be
used when a high-pass lter will be applied in a DSP upstream of the amplier.
Connections
7 Speaker output connectors (see figure 3)
Wire the speakers to the amplier output using the included 2-pole, 5.08 mm captive screw connectors
(see gure 4, A). Each port has a screw ange to secure the plug to the connector (B).
Do not tin the wires!
CLASS 2 WIRING
Figure 4. Connecting Speaker Outputs
ATTENTION:
• Do not tie channel output pins to each other or to ground. Doing so will short out the outputs, damage the
amplier, or both.
• Ne pas lier les sorties 1 et 2 des canaux entre elles ou à la terre. Les sorties pourraient être court-circuitées et/ou
l’amplicateur pourrait être endommagé.
• To avoid risk of damage to the ampliers or speakers, ensure that the amplier output mode selection switch for
each channel is properly congured to match the type of speaker load about to be connected to the particular
output.
• Pour éviter tout risque de détérioration des amplicateurs ou des enceintes, assurez-vous que le switch de
sélection du mode de sortie de l’amplicateur est correctement conguré pour s’adapter au type de charge de
l’enceinte qui sera connectée à la sortie donnée.
NOTE: You must use Class 2 wiring for this output to comply with UL requirements.
8 Line inputs (see figure 3)
Use 5-pole 3.5 mm captive screw connectors to input four (XPA U 2004 FX) or eight (XPA U 2008 FX) channels of balanced or
unbalanced line-level audio signals through these connectors.
Wire the source output to the captive screw connectors as shown in the following illustrations.
Tip
Ring
Tip
Ring
ves
12
Tip
Sleeve
Sleeve
Tip
12
Do not tin
the wires!
Balanced Dual Mono Input
Tip
Ring
Sleeve (s)
Tip
Ring
12
Unbalanced Dual Mono Input
Tip
Sleeve
Tip
Sleeve
12
Output Mode Selection Switch
(HPF OFF)
70V 70V
100V
100V
8Ω
4Ω
OUTPUT MODE
Speaker output connectors
Line inputs