XPA U 1004 SB and XPA U 2002 SB • Operation
15
NOTE:
XPA U 2002 SB shown. Channels 3 and 4 of the XPA U 1004 SB are
configured in the same way.
D
— (see
page 14) Each channel features a 8-position rotary switch
to set the output mode for specific channels (see figure on
the right). The bottom switch controls channels 1 and 2,
and the XPA U 1004 SB has a top switch that controls
channels 3 and 4. There are eight settings that are divided
into stereo and bridged mono:
•
Stereo Mode (4 ohm/8 ohm)
— Each channel of a output pair behaves
independently, and each input is routed to its respective output. A channel’s level is
set by its dedicated attenuator.
•
Bridged Mono Modes
— There are six bridged mono modes: two low-impedance
(8 ohm and 16 ohm bridged) and four high-impedance (70V, 70V with no HPF,
100V, and 100V with no HPF)
In all six mono modes, the outputs of a pair are bridged, and the lowest-numbered
channel is fed to the pair’s positive pins. The bridged output’s positive pin is now
the lowest-numbered channel’s pin. And the higher-numbered output’s positive pin
becomes the bridged output’s negative pin.
The level is set by using the attenuator on the lowest-numbered channel. The
higher-numbered channel’s input and attenuator are not used in bridged mono
mode.
In either 70V or 100V modes, an 80 Hz, 12 dB/octave high-pass filter is applied
to the signal. This can be disabled by selecting (HPF OFF) for either 70V or 100V
mode. On 8 ohm and 16 ohm bridged modes, the filter is disabled.
NOTE:
In 70V/100V output modes, HPF should be disabled at the amplifier
only if a high-pass filter will be applied upstream of the amplifier.
E
— (see
on page 14) Wire the amplifier input connectors based
on the output. See Figure 16 for details on how to wire the input connectors.
NOTE:
In bridged mono output modes, even-numbered channels are not used in
the connector.
F
— (see
Connect up to two 4-pin, 5mm captive screw connectors for up to
four channels of speaker outputs. Each port has a screw flange to
secure the plug to the connector. Observe the correct polarities for
each channel as shown to the right.
OUTPUT MODE
1 & 2
BRIDGED
MONO
70V
70V (HPF OFF)
100V
100V (HPF OFF)
STEREO
4Ω
8Ω
8Ω
16Ω
Summary of Contents for XPA U 1004 SB
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