The JBL DrivePack® Input Compressor panel can be accessed by double-clicking on the COMP button control in the Input control Sub-Panel.
The settings contained within this panel can be copied by selecting the COMP button and performing a copy using the CTRL-C command or by using the Edit -> Copy command on the Operator Advanced control panel menu. The copied setting can the be pasted to another device by opening the Operator Advanced control panel for the target device and selecting the COMP button and performing a paste using the CTRL-V command or by using the Edit -> Paste command on the Operator Advanced control panel menu.
Users can compress input signals to desired levels using this function. The user can enable/disable the function, set the compression ration, make-up gain and attack and release time. The user can also make use of standard compression presets.
The user can enable and disable the Compressor by clicking the On/Off button control. The Compressor state is indicated by the button control text and color.
– When the Compressor is enabled the Compressor button control is colored green and the text is "On".
– When the Compressor is disabled the Compressor button control is colored gray and the text is "Off".
The Threshold control sets the level that the input must exceed before compression is activated. The value can be set either through the numeric spin box or by dragging the handle in the graph.
The compression ratio controls the amount of compression that is applied for each step of input above the threshold. The range of control is 2:1 through 32:1. You can set the compression ratio in two ways: either by using the display handle at the right of the chart to set the ratio or the dedicated Compression Ratio numeric spin control.
The Gain Reduction Meter indicates how much the level is being reduced by the Compressor. The meter indicates more reduction by showing the meter moving downward.
This control will allow you to determine a “soft roll on” where the compressor is gradually modified from the unity gain to the final compressed gain. The spin control is used to set a range in dB before the actual threshold through which the compressor gain is gradually modified from unity to the final compressed gain.
The Attack Time control sets the amount of time it takes to attenuate the input signal from unity gain to the amount of reduction indicated by the ratio. The range of control is 10 milliseconds through 2 secs.
The Release Time control sets the amount of time it takes to increase back to unity gain (no change) after the input signal has dropped below the threshold. The range of control is 100 milliseconds through 30 secs.
The user can enable one of the provided Compressor presets by clicking on one of the preset button controls.
Slow – Attack Time = 0.100 seconds, Release Time = 0.60 seconds.
Medium – Attack Time = 0.050 seconds, Release Time = 0.30 seconds.
Fast – Attack Time = 0.025 seconds, Release Time = 0.20 seconds.
This numeric spin control has a range of 0dB of gain (unity) to +20dB of gain. The step size is .5 dB.