User Guide

FXAlg #954: Compress/Expand ¥ FXAlg #955: Comp/Exp + EQ
Algorithm Reference-150
PAGE 4 (Comp/Exp + EQ only)
In/Out When set to ÒInÓ the compressor/expander is active; when set to ÒOutÓ the
compressor/expander is bypassed.
Out Gain Compressing the signal causes a reduction in signal level. To compensate, the output
gain parameter may be used to increase the gain by as much as 24 dB. Note that the Out
Gain parameter does not control the signal level when the algorithm is set to ÒOutÓ.
FdbkComprs A switch to set whether the compressor side chain is conÞgured for feed-forward (Out)
or feedback (In). The expander is unaffected.
Comp Atk The time for the compressor to start to cut in when there is an increase in signal level
(attack) above the threshold.
Comp Rel The time for the compressor to stop compressing when there is a reduction in signal
level (release) from a signal level above the threshold.
Exp Atk The time for the expander to increase the gain of the signal (turns off the expander) after
the signal rises above threshold.
Exp Rel The time for the expander to reduce the signal level when the signal drops below the
threshold (turning on expansion).
SmoothTime A lowpass Þlter in the control signal path. It is intended to smooth the output of the
expanderÕs envelope detector. Smoothing will affect the attack or release times when the
smoothing time is longer than one of the other times.
Signal Dly The time in ms by which the input signal should be delayed with respect to compressor
side chain processing (i.e. side chain pre-delay). This allows the compression to appear
to take effect just before the signal actually rises.
Comp1Ratio The compression ratio in effect above compression threshold #1 (Comp1Thres). High
ratios are highly compressed; low ratios are moderately compressed.
Comp1Thres One of two compression threshold levels. Threshold is expressed in dBFS (decibels
relative to full scale) above which the signal begins to be compressed.
Comp2Ratio The compression ratio in effect above compression threshold #2 (Comp2Thres). High
ratios are highly compressed; low ratios are moderately compressed.
Comp2Thres One of two compression threshold levels. Threshold is expressed in dBFS (decibels
relative to full scale) above which the signal begins to be compressed.
Exp Ratio The expansion ratio. High values (1:17 max) are highly expanded, low values (1:1 min)
are moderately expanded.
Exp Thres The expansion threshold level in dBFS (decibels relative to full scale) below which the
signal begins to be expanded.
MakeUpGain Provides an additional control of the output gain. The Out Gain and MakeUpGain
controls are additive (in decibels) and together may provide a maximum of 24 dB boost
to offset gain reduction due to compression or expansion.
Bass Gain -79.0 to 24.0 dB Treb Gain -79.0 to 24.0 dB
Bass Freq 16 to 25088 Hz Treb Freq 16 to 25088 Hz
Mid Gain -79.0 to 24.0 dB
Mid Freq 16 to 25088 Hz
Mid Wid 0.010 to 5.000 oct