Considerations; Ground Loops; Audio Connections; Background Noise - Ecler MAC90i Manual De Instrucciones

5. CONSIDERATIONS

5.1. Ground loops

You should always try that all sources which reach the mixer, as well as all devices
connected to its output, do not have their grounds interconnected between them, that is, that they
never get the ground signal through two or more different ways. Sould this ever happen, hum and
noise could appear and interfere the sound quality.
The cable shieldings, when connected to the chassis, must never be interconnected
between them. This way ground loops will be avoided.

5.2. Audio connections

As a general rule of thumb, make the signal connections as short as possible and use the
best connectors and cable available. Cables and connectors are frequently undervaluated, forgetting
that a bad connection can result in a poor sound quality.

5.3. Background noise

The use of active circuitry can yield, depending on the configuration, to a significant noise
level. The MAC90i mixer has been designed for the minimum possible noise. Anyway, the noise
level will always depend on the correct use and installation of the mixer.
It is not the same setting up the "FADER" "2" and the "MASTER" at "10" that the other way
round; "FADER" at "10" and "MASTER" at "2". In the first case you get a poor signal-to-noise ratio
that will be fully amplified by the master while on the second we have a good signal-to-noise ratio
only amplified by 2. As a result, the background noise is greater in the first case than in the second
one.

5.4. Cleaning

The control panel must not be cleaned with any dissolvent, abrasive or petroleum
derivated 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 mixer, do not use any cleaning sprays; send the unit to the
nearest ECLER Technical Service.
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