Nilfisk-ALTO CLE8.0 user manual Attack control, Output control

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If you have a ratio of 2:1 this means that for every 2dB increase of the input level (above threshold) you will get an increase of output level of 1dB. ON the same way, a ratio of 10:1 means that for every 10dB increase of the input level (above threshold) you will get an increase in output level equal to 1dB, and so on.

You need to be aware that higher ratio settings produce less natural sounds so if you wish a more minute effect on the dynamic range of a program you should use a Ratio of 4:1 or lower.

With the SKC circuit (Smart Knee Control) you can avoid aggressive compression generated by using high ratios. How we achieve this? Introducing a "soft knee" curve in the range of up to 10dB above the threshold level. Hard Knee compression is then used beyond this range.

Output

 

 

Threshold

Gain 0 dB

 

 

 

Ratio 2:1

 

Hard Knee

Ratio 4:1

 

 

 

 

Limiter

:1

SKC Cur ve

 

 

 

Input

Chart.5: SKC characteristic of the compressor section

4.2.3Attack control

The attack time represents the amount of time that passes before the compressor start to lower the output level when the signal is above the threshold point. For very fast transients such as drums, handclaps, etc. a short attack time will be used. These peaks are consequently carefully regulated by the compressor.

Sounds of other nature will get advantages if longer attack times are used. Anyway, our advice is always to begin the process with longer attack times. Then you can start gradually to reduce the attack time. In the CLE 8.0 the attack time can be set in a range of 1 to 150 milliseconds.

4.2.4Release Control

This control determines how much time the compressor needs to get back to normal gain when the audio signal falls below the set threshold.

A too short release time will make the volume to fluctuate and you will experience pumping effect. A too long release time will give you pumping and breathing effect especially when you have loud passage followed by a quite passage. The release time on CLE 8.0 can be set from 0.05 to 5 seconds.

4.2.5Auto switch

This switch turns off the possibility of manually set the attack and release times. An intelligent program re- cognition circuit will automatically set the attack and release times. In such way, undesirable effects such as distortion and pumping will be avoided.

4.2.6Output control

This Control is indispensable to compensate the loss of level at output level generated by the gain reduction caused by the compression and limiting processing

4.2.7Bypass Switch

This switch simply turns off the processing of the corresponding channel. This is useful to compare quickly the processed and unprocessed signal.

4.2.8Gain Reduction Meter

This consists of 8 LED on the front of the CLE 8.0. Through this Led meter you can visualise the amount of gain reduction at any given time.

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Contents CLE8.0 Safety Related Symbols Important Safety InstructionsPower Supply External ConnectionPreface Table of Contents Introduction Concept BehindSome technical stuff Introducing Audio Dynamics More technical stuff about Compressor/LimitersControls Master Control SectionMore about noise Expanders and Noise-Gates Take it easy Balanced InputsBypass Switch Input / Output Meter SwitchSC Filter switch Smart switchAuto Switch Compressor ControlCompressor LED Attack ControlPeak Limiter Control Peak Limiter LEDAC Inlet and Fuse Holder Audio1 EXP/GATE Adjustment Expander/Gate SectionAnother Threshold Control? Output control Installation and Connection Mains ConnectionWiring Configuration Line ConnectionInsert Points Connection Insert LeadsTechnical Specifications InputPhysical Warranty Warranty Registration CardSeikaku Technical Group Limited