Emulator Composite.book - Creative

9 - Effects
Effects Descriptions
Compressor
In its simplest form, an audio compressor is just an automatic gain control. When the
volume gets too loud, the compressor automatically turns it down. Compressors are
useful in musical applications because they smooth out dynamic volume changes and
provide a louder average signal level.
0dB
-30dB
-80dB
Threshold: -30dB
Ratio
1:1
1.5:1
2:1
10:1
Since the compressor turns down the gain of the signal, you might wonder how can it
make the signal level stronger. An Output Gain control allows you to boost the output
gain of the compressor in order to make up for the gain reduction. The overall level is
higher and only turned down when the signal level gets too loud. The level at which the
volume gets turned down is called the Threshold, which just happens to be the most
important control on the compressor.
Basic Controls
The three main controls of a compressor are the Ratio control, the Threshold control
and the Output Gain control.
In
Signal Level
Signal path = Stereo
Level
Control
VCA
Threshold Output Gain
Ratio Attack Release
If the signal falls below the Threshold, no processing will take place. Signals exceeding
the Threshold will have gain reduction applied as set by the ratio control. This
important control allows you to dial in the range of amplitudes you want to tame. For
example, if you’re trying to trim off just the loudest peaks, set the threshold high so
that compression only occurs during these peaks. One of the biggest mistakes in
using a compressor is having the threshold set too low. This adds noise as the
compressor will always be reducing the volume.
226 Emulator X2 Operation Manual
Out