4.2. Input attenuation
These are rotary trimmers located on the front panel (1, 4, 7, 10, 13, 16).
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 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.
4.3. Remote control
The MPA R rear panel offers one terminal per amplifier to remotely control the volume, using the
built-in "VCA" circuit.
The combined usage of the rotary potentiometers located at the front panel and the remote VCA
control determines the final value of the signal's attenuation for each input channel. Therefore, a certain
value can be fixed for the signal attenuation using the rotary so that the remote control via VCA will not
exceed this value and viceversa, that is, the two controls are connected in series.
This functionality can be useful in installations where users with little experience are in charge of
volume adjustment.
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