Output Connections; Operation And Usage; Start Up; Input Attenuation - Ecler MPA4-80 Bedienungsanleitung

3.6. Output connections

The output section on the MPA4-80 rear panel holds 8 screw-type speaker terminals (23,
24, 25, 26), two for each amplifier.
The attenuation controls and the output configurations are described later in paragraph
6.4.
The output section on the MPA6-80 rear panel holds 12 screw-type speaker terminals (21,
22, 23, 24, 25, 26), two for each amplifier.
The attenuation controls and the output configurations are described later in paragraph
6.5.
The cable which connects the speakers to the amplifier should be high quality and as short
and thick as possible. This is important when covering long distances; for up to 10m we recommend
a cable section not smaller than 2.5mm². For longer distances we recommend 4mm².
Remember that the minimum load impedance for stereo or mono amplifiers is 4. In
bridged mode the impedance must be not less than 8. For a reliable operation under any
circumstance connect lower load impedances than just specified.
Attention: In bridged mode, use only the red terminals.

4. OPERATION AND USAGE

4.1. Start up

To switch the unit on just push the switch labelled POWER (19) and the integrated green
pilot light will light up. We highly recommend the "safe power up sequence": First the sound sources,
then mixer, equalizers and active filters and, finally, power amplifiers. Powering off should be done
by following the exact reverse sequence in order to avoid any possible peaks reaching the next
device, and consequently protecting the loudspeakers, which are specially sensitive to these peaks.

4.2. Input attenuation

These are rotary potentiometers located on the front panel (1, 4, 7, 10 on the MPA4-80
and 1, 4, 7, 10, 13, 16 on the MPA6-80).
These attenuators allow the connection of different mixers, an independent volume control
and the connection of speakers not able to handle the amplifiers maximum output power, thus
avoiding the risk of damaging them with the mixers or preamps volume control.
Inside the device's packaging you will find a little plastic bag containing 4/6 transparent
caps which protect the input attenuation settings from unwanted manipulation. These caps are
transparent in order to let you visualize the current settings.
Once inserted, they cannot be removed with bare fingers, for this purpose, a small screwdriver is
needed.
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