Expansion - Kurzweil Forte Manual

The Effects Chain Editor
Effects Parameters
FdbkComprs (Feedback Compression) selects whether to use feed-forward (set this to
"Out") or feed-back (set this to "In") compression. The feed-forward configuration uses the
input signal as a side-chain source, which is useful when the compressor has to act really
quickly. The feed-back configuration uses the compressor output as the side-chain source,
which lends itself to more subtle, but not as quick-reacting, compression.
Atk (Attack) Time for the compressor is adjustable from 0.0 to 228.0 ms. Rel (Release) Time
for the compressor is adjustable from 0 to 3000 ms.
SmoothTime smooths the output of the expander's envelope detector by putting a lowpass
filter in the control signal path. Smoothing will affect the Attack or Release times only when
this parameter is longer than one of the other times. The range is 0.0 to 228.0 ms.
Signal Dly (Delay) puts a small delay in the signal relative to the sidechain processing, so
that the compressor (or gate) "knows" what the input signal is going to be before it has
to act on it. This means the compression can kick in before an attack transient arrives. In
the SoftKneeCompress and HardKneeCompress effects, delay is really only useful in feed-
forward configuration (FdbkComprs is "Out"). For other compressors, the delay can be
useful in feedback configuration (FdbkComprs is "In"). The range is 0 to 25 ms.
Ratio is the amount of gain reduction imposed on the compressed signal, adjustable from
1.0:1 (no reduction) to 100:1, and Inf:1.
Threshold is the level in dBFS (decibels relative to full scale) above which the signal begins
to be compressed. Adjustable from -79.0 to 0 dB.
MakeUpGain allows additional output gain to compensate for gain reduction in the
compressor. It is essentially the same parameter as Out Gain, with which it is summed. The
minimum is -79.0, and the maximum summed gain (MakeUpGain + Out Gain) is +24.0
dB.

Expansion

Effects containing Expanders have these controls:
Atk or Exp Atk (Attack), how fast the expander turns off when the input signal rises above
the threshold level, adjustable from 0.0 to 228.0 ms.
Rel or Exp Rel (Release), how fast the expander turns back on after the signal drops below
the threshold level, adjustable from 0 to 3000 ms.
Ratio or Exp Ratio, how much the gain is reduced below the expansion threshold, adjustable
from 1:1.0 (no expansion) to 1:17 (extreme downward expansion).
Threshold or Exp Threshold, the level below which the signal is expanded, adjustable from
-79.0 to 0 dB.
In addition, the two-segment compressors with expander have separate Ratio and Threshold
controls for each of the compression segments.
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