Considerations; Ground Loops; Audio Connections; Background Noise - Ecler SMAC PRO20 Notice D'emploi

5. CONSIDERATIONS

5.1. Ground loops

Ensure at all times that no signal sources reaching the mixing desk and no devices
connected to its output have their earths interconnected; that is, earth should never reach them via
two or more different paths, as this coul lead to humming which could even interfere with sound
reproduction quality. In order to avoid earth loops, ensure that the shieldings of cables, if connected
to the chassis, are never connected with each other.

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 SMAC series mixers have 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" at "2" and the "MASTER" at "10" that the other
way round; "FADER" at "10" and "MASTER" at "2". In the PRO20 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 PRO20 case than in the
second one.

5.4. 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 unit through the holes of the front
panel.
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