MOTU UltraLite-mk4, Руководство пользователя

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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 8-5)
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 8-5) 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.
Compressor graph
The Compressor graph below the Compressor
section (Figure 8-5) provides a thumbnail visual
indication of the current compressor settings for
the input channel. It is for visual reference only and
cannot be edited directly. However, you can click it
to open the full-size Compressor graph in a
separate window (Figure 8-6), which provides
graphic editing of the Ratio and Threshold
controls.
Threshold
handle
Figure 8-6: The full-size Compressor graph.
Ratio handle