MOTU 828es, User Manual

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M I X E R E F F E C T S
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the signal to 2 dB above the Threshold. When the
input level goes above the threshold, the
attenuation is added gradually to reduce
distortion. The rate at which the attenuation is
added is determined by the
Attack parameter.
Likewise, when the input level falls below the
Threshold, the attenuation is removed gradually.
The rate at which the attenuation is removed is
determined by the
Release parameter. Long
Release times may cause the audio to drop out
briefly when a soft passage follows a loud passage.
Short Release times may cause the attenuation to
“pump”, a term used to describe the sound of the
compressor when the average input level quickly
fluctuates above and below the Threshold. These
types of issues can be addressed by adjusting the
compressor’s parameters, or applying the Leveler
instead.
Gain adjusts the overall output level of the
compressor, post processing. The Level meter
(Figure 9-5) shows the level of the input signal
entering the compressor. It shows either the Peak
envelope or the RMS level, if enabled.
Gain reduction meter
The Gain reduction meter (Figure 9-5) displays
the current amount of attenuation applied by the
compressor, before the makeup gain stage.
RMS mode
By default, the compressor operates in Peak mode,
which uses signal peaks to determine the input
level. In RMS
mode, the compressor measures the
input signal’s loudness, using the root-mean-
square computational method. When RMS is
disabled, RMS mode will let brief peaks through
because the detector sidechain is only looking at
the average signal level. By contrast, peak mode
will catch those brief peaks. Peak mode is
generally used for drums, percussion and other
source material with strong transients, while RMS
mode is mostly used for everything else.
The level meter shows either the peak level or the
RMS level, depending on the mode.
Auto Makeup
When Auto Makeup Gain is engaged (Figure 9-5
and Figure 9-6), the compressor dynamically
compensates for any gain reduction, to preserve
the original loudness of the signal.
Threshold
handle
Figure 9-6: The full-size Compressor graph.
Ratio handle