Installation; Rack Installation; Connecting The Amplifier - Omnitronic MCR-4250 Bedienungsanleitung

6. INSTALLATION

Please note: when using a PA-system in public or industrial areas, a series of safety instructions have to be
followed that this manual can only give in part. The operator must therefore inform himself on the current
safety instructions and consider them.

6.1 Rack installation

This amplifier is built for 19" racks (483 mm). The rack you use should be a Double-Door-Rack where you
can open the front panel and the rear panel. 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.
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. In this way, the amplifier cannot be pushed backwards.
The front panel alone is not designed to absorb acceleration forces occurring during transportation.

7. CONNECTING THE AMPLIFIER

All connections have to be made or changed only if the amplifier is switched off!
Occupation balanced XLR-connector: Occupation CAT5 cable:
7.1 Inputs
Connect the output of a preamplifier or a mixer to the INPUT jacks on the rear panel. In bridge mode, use
CH1 and/or CH3 only. A good cable run improves the sound quality remarkably. Input cables should be short
and direct, since high frequencies will mostly be absorbed if the cables are unnecessarily long. Besides that
a longer cable may lead to humming and noise trouble. If long cable runs are unavoidable, you should use
balanced cables.
7.2 Outputs
DANGER TO LIFE!
High voltage at terminals. Switch off amplifier before connecting!
In stereo mode, the amplifier can operate four speakers or four speaker groups. The amplifier can be
switched over to bridge operation to supply the double output power. Then it operates as 2-channel amplifier
and supplies 2 x 450 W to two 8 speakers or two 8 speaker groups. Connect your speakers via speaker
or screw connectors.
The high damping factor of your amplifier supplies a clear sound reproduction. Unnecessarily long and thin
cables will influence the damping factor and thus the low frequencies in a negative way. In order to
safeguard good sound quality, the damping factor should lie around 50. The longer a cable has to be, the
thicker it should be.
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