2009

Table Of Contents
Compressor Threshold slider and field: Sets the threshold level—signals above this
threshold value are reduced in level.
Peak/RMSbuttons: Determines whether signal analysis is with the Peak or RMS method,
when using the Platinum circuit type.
Gain slider and field: Sets the amount of gain applied to the output signal.
Auto Gain pop-up menu: Choose a value to compensate for volume reductions caused
by compression. The choices are Off, 0 dB, and −12 dB.
Limiter Threshold slider and field: Sets the threshold level for the limiter.
Limiter button: Turns the integrated limiter on or off.
Output Distortion pop-up menu (Extended Parameters area): Choose whether to apply
clipping above 0 dB, and the type of clipping. Choices are: Off, Soft, Hard, and Clip.
Activity pop-up menu (Extended Parameters area): Enables or disables the side chain.
Choices are: Off, Listen, and On.
Mode pop-up menu (Extended Parameters area): Choose the type of filter used for the
side chain. Choices are: LP (lowpass), BP (bandpass), HP (highpass), ParEQ (parametric),
and HS (high shelving).
Frequency slider and field (Extended Parameters area): Sets the center frequency for the
side-chain filter.
Q slider and field (Extended Parameters area): Sets the width of the frequency band
affected by the side-chain filter.
Gain slider and field (Extended Parameters area): Sets the amount of gain applied to the
side-chain signal.
Mix slider and field (Extended Parameters area): Determines the balance between dry
(source) and wet (effect) signals.
Using the Compressor
The following section explains how to use the main Compressor parameters.
Setting the Compressor Threshold and Ratio
The most important Compressor parameters are Threshold and Ratio. The Threshold sets
the floor level in decibels. Signals that exceed this level are reduced by the amount set
as the Ratio.
The Ratio is a percentage of the overall level; the more the signal exceeds the threshold,
the more it is reduced. A ratio of 4:1 means that increasing the input by 4 dB results in
an increase of the output by 1 dB, if above the threshold.
As an example, with the Threshold set at −20 dB and the Ratio set to 4:1, a −16 dB peak
in the signal (4 dB louder than the threshold) is reduced by 3 dB, resulting in an output
level of −19 dB.
92 Chapter 4 Dynamics Processors