Kurzweil PC3, Руководство музыканта

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Effects
Compressors, Expanders, and Gates
9-15
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 algorithms, 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 (Make Out Gain) is +24.0 dB.
Expansion
Algorithms 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.
Multiband Compression
The Multiband Compression algorithm has Attack , Release , Smooth , Signal Delay , Ratio ,
Threshold , and MakeUp Gain parameters for each of the three bands (“Low”, “Mid”, and
“High”). In addition, it has:
Crossover1 and Crossover2 . These set the frequencies which divide the three compression
frequency bands. The two parameters are interchangeable, so either may contain the higher
frequency value. The range is 16 to 25088 Hz, in increments of a semitone.
Gates
SC Input lets you select which input channel(s) will control the sidechain, which is responsible
for opening and closing the gate. It can be set to L, R, or the average of the two channels,
(L+R)/2. You can use this, if you arrange the signal paths and pan controls appropriately, to gate
one mono signal with a different mono signal—the venerable “Keyfex” effect.