Ecler MPA6-150, User Manual

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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 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.
4.3. Indicators
The SP signal presence indicators (2, 5, 8, 11, 14, 17) light up when the input signal
reaches approximately -40dBV.
The CLIP indicators (3, 6, 9, 12, 15, 18) light up when the output signal for the speakers is
-1.5dB below the actual clipping threshold. This clipping system watches for eventual supply voltage
variations, thus giving always an accurate clipping indication, regardless of mains voltage deviations.
It is normal that when operating at high output power, the CLIP indicators light up in
synchronisation with the low frequencies, which carry the most energy. Nevertheless, you should
avoid that the CLIP indicators are lit continuously.
Thermal protection indicator “THERMAL” (19), it shines when the cooling tunnel temperature
reaches 90ºC. The amplifier will automatically restart when the temperature lessens to 80ºC.
5. CLEANING
The front panel should not be cleaned with dissolvent or abrasive substances because silk-
printing could be damaged. To clean it, use a soft cloth slightly wet with water and neutral liquid soap;
dry it with a clean cloth. Be careful that water never gets into the amplifier through the holes of the front
panel.
SP
CHANNEL 3
10 0 VOL VOL 0 10 0 10 VOL
CHANNEL 1
5
CLIP SP
CHANNEL 2
5
SP CLIP
5
10 0 VOL VOL 0 VOL 10 0 10
CHANNEL 5 CHANNEL 4
CLIP
5
CLIP SP
5
CHANNEL 6
CLIP SP SP
5
THERMAL CLIP