Setup; Rack Installation; Making The Connections - Omnitronic XPA 350 User Manual

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SETUP

Rack Installation

This amplifier is built for 19" racks (483 mm). This rack use should be a double-door rack where front panel
and rear panel can be opened. The rack should be provided with a cooling fan. When mounting the amplifier
into the rack, please make sure that there is enough space around the device so that the heated air can be
passed on. Steady overheating will damage your device.
You can fix the amplifier with four screws M6 in the rack. If several devices are to be installed, make sure
that you leave 1 unit space between the devices.
Be careful when mounting the amplifier into the rack. Put the heaviest devices into the lower part of the rack.
Be aware that fastening the amplifier with four screws on the front panel is not enough. In order to ensure
safety, additional fastening by using ground and side bars is necessary.
If racks are to be transported or used for mobile use, additionally fasten the devices by connecting the rear
brackets with the side or ground bars of the rack. Thus, the amplifier cannot be pushed backwards. The front
panel alone is not designed to absorb acceleration forces occurring during transportation.

Making the Connections

All connections have to be made or changed only if the amplifier is switched off!
1) Inputs: The connection of the inputs depends on the operating mode selected. Therefore, prior to
making any connections, select the operating mode according to your desired application. Then
connect the output of line signal sources (e.g. preamplifier or mixer) to the XLR inputs or 6.3 mm
jack/RCA inputs.
2) Speaker outputs: In stereo and parallel mode (only XPA-1800/27000), the amplifier can operate two
speakers or two speaker groups. For connecting speakers, Speaker jacks and pairs of screw terminals
are provided. When using the Speaker jacks, turn each plug to the right until it locks into place. For
unlocking, pull the unlock button and turn the plug to the left. The amplifier can be switched over to
bridge operation to supply the double output power. Then it operates as 1-channel amplifier and
supplies power to one 8 Ω speaker or one 8 Ω speaker group. In this case, use the red Speaker jack or
the two red terminals for the connection.
Model XPA-3004: In stereo and parallel mode, this model can operate four speakers or four speaker
groups. To double the output power, channels 1, 2 and/or 3, 4 can be bridged to drive one speaker or
speaker group each. For connecting speakers, Speakon jacks are provided.
Notes: Always use sufficiently dimensioned cables (min. 2.5 mm²). When interconnecting several
speakers, it is especially important to consider the correct connection to positive and negative contacts
and that the minimum total impedance is 4 Ω for stereo and parallel operation, and 8 Ω for bridge
operation. Please refer to skilled personnel if you are not familiar with the connection of several
speakers.
3) Pow er supply: Finally connect the amplifier to a mains outlet with the mains cable.
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