4. OPERATION AND USAGE
4.1. Start up
To switch the unit on just push the switch labelled POWER (14) 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 trimmers located on the front panel (1, 4, 7, 10).
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 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) light up when the input signal reaches
approximately -40dBV.
The CLIP indicators (3, 6, 9, 12) 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.
5. CLEANING
The control panel must not be cleaned with any dissolvent, abrasive or petroleum
derivate substance else paint and silk printing could be damaged.
Whenever cleaning should be necessary use a soft cloth slightly wet with water and
neutral liquid soap or with a solution of water and alcohol at 50%. Be careful that no liquid gets
into the mixer. Never use sharp or erosive objects to scratch the control panel.
Should any liquid get into the amplifier, do not use any cleaning sprays; send the unit
to the nearest ECLER Technical Service.
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