E-Mu 1212m Owner's Manual page 93

0dB
-20dB
-80dB
This diagram shows the effect of varying the Soft Knee Threshold. Compres-
sion is 1:1 (no compression) at the Knee Threshold and smoothly transforms into the
selected compression ratio at the Compression Threshold. The upward arrow shows
the additional gain added to signals below the Threshold.
0dB
-20dB
-35dB
-80dB
This diagram shows the effect of varying the Compression Ratio with a
fixed Soft Knee Threshold. The knee transforms from a linear slope to the slope of
the compression ratio over the Soft Knee Threshold area. The upward arrow
shows the additional gain added to signals below the Threshold.
In the region between the lower knee and upper Threshold, a variable amount of gain
reduction is applied depending on the signal level and Ratio setting. To keep this gain
reduction from "dragging down" the signal levels at the Threshold point, a comple-
mentary gain boost is automatically applied to all signal levels below the Threshold
when the Soft Knee is enabled. This gain increase with depth and Ratio is illustrated by
the upward arrows in the diagrams, and is similar to the action of the Auto Makeup
Gain parameter. Thus signal levels below the Threshold increase as the Soft Knee depth
and/or Ratio is increased (but see the Gate parameter, below.)
E-MU PCI Digital Audio Systems
Soft Knee
(Varying the Soft Knee Threshold)
Threshold: -20dB
Ratio = 4:1
Soft Knee
(Varying the Compression Ratio)
Threshold: -20dB
Soft Knee:
Threshold -15dB
Knee
Threshold -10dB
Threshold -20dB
Threshold -30dB
Ratio = 1.5:1
Ratio = 4:1
Ratio = 10:1
5 - Effects
Core Effects Descriptions
Tip: Setting a high
Ratio with the Threshold at
0dB and the Soft Knee at -
60dB creates a compressor
whose ratio varies
smoothly from gentle
compression at lower
signal levels to peak
limiting at maximum signal
level
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