Nilfisk-ALTO CLE8.0 Expander/Gate Section, 1 EXP/GATE Adjustment, Another Threshold Control?

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4.READY TO ROLL?

4.1Expander/Gate Section

Chart.3: Function of an expander

As we told you previously in this Manual the downward expander will reduce automatically the level of the audio signal when such signal is below a set threshold. So the expander is the opposite of the compressor/limiter. We also explained to you how the ratio curve of the expander is flat while a noise gate it is more brutal processor: It simply cut-off the entire signal below a certain set threshold. The CLE 8.0 is equipped with a new kind of expander, the SRC (Smart Ratio Control). The ratio of the SRC is automatically adjusted according to the audio signal level. In fact, conventional expanders could easily cut part of the musical program with unacceptable result: The gain changes become audible. We have equipped the SRC with a non-linear ratio curve, which is soft and adjustable by the User. Thanks to the SRC low passages close to noise floor level will be processed with a minimum ratio of expansion while for signals of reduced level a higher ratio will be used with resultant greater attenuation.

SRC CURVE

Chart.4: SRC Curve characteristics of the Adaptive Expander

4.1.1EXP/GATE Adjustment

The EXP/GATE control covers a very wide range and it is efficient with any working level. Turn the threshold control fully counterclockwise and the Expander/Gate section will be completely off.

4.2Compressor Section

4.2.1Another Threshold Control?

The compressor threshold control sets the point where the input level starts to be reduced. Let's say the level is +12dBu and the threshold control is set at +2dBu: In this case up to 10dB can be compressed. If the input level is the same and the control is set at -10dBu the maximum compression will be 22dB, The operating range of the threshold control is -40 to +20dBu. Turn the threshold control fully clockwise and you will get a threshold level of +20dBu.

You must remember that the degree and the type of compression not only depend by the threshold control but also by other controls such as Ratio, Attack and Release.

4.2.2Ratio control

This control sets the change of input level to output level but only for the signals that exceed the threshold. The scale of the ratio control on the front panel (calibrated in dB) indicates how much input level is required to increase the output level by 1dB. If you have a ratio equal to 1:1 you will get the same level of input and output signal: So, no level change.

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Contents CLE8.0 External Connection Safety Related SymbolsImportant Safety Instructions Power SupplyPreface Table of Contents Some technical stuff IntroductionConcept Behind More technical stuff about Compressor/Limiters Introducing Audio DynamicsTake it easy Balanced Inputs ControlsMaster Control Section More about noise Expanders and Noise-GatesSmart switch Bypass SwitchInput / Output Meter Switch SC Filter switchAttack Control Auto SwitchCompressor Control Compressor LEDAudio Peak Limiter ControlPeak Limiter LED AC Inlet and Fuse HolderAnother Threshold Control? 1 EXP/GATE AdjustmentExpander/Gate Section Output control Mains Connection Installation and ConnectionLine Connection Wiring ConfigurationInsert Leads Insert Points ConnectionInput Technical SpecificationsPhysical Warranty Registration Card WarrantySeikaku Technical Group Limited