5 - Effects
Core Effects Descriptions
90
Creative Professional
RFX Compressor
The RFX Compressor is a full-featured stereo compressor effect which features the standard
parameters available on most compressors as well as a collection of additional advanced
parameters that are useful for more sophisticated applications and special effects:
• Threshold, Ratio, Attack and Release w/gain metering
• Auto-makeup gain
• Adjustable soft knee
• Adjustable lookahead/delay
• Noise gate (downward expander)
• Compressor “tail” expansion
• Program-dependent release
• Negative compression ratios
Signal Flow
The block diagram of the RFX Compressor is shown below.
Note that the effect is split between a signal path and a sidechain path that contains the
compressor's level detectors and gain computation. The signal path of the RFX
Compressor is very close to a “straight wire”, with only a delay line and one gain control
element inserted in it. The sidechain contains the bulk of the compressor algorithm and
is responsible for computing the gain control signal. Signal multiplexers at the front of
the signal path and sidechain allow linked stereo compression or split signal path/
sidechain processing.
The RFX Compressor does not have the input gain control that is found on some
compressors. These are typically used to align the input signal range to the compression
threshold. Instead, we've allowed the RFX Compressor's Threshold parameter to operate
over an exceptionally large range of 0-60dB so that it can be “steered” to the appropriate
range of the input signal. The output Gain parameter also operates - either manually or
automatically - over the unusually large range of -60dB to +60dB in order to renor-
malize the compressor's output for the next stage of the signal path.
In L
In R
Out
L
R
Out
Compressor
Lookahead
0-100mS
Compressor
Delay
Attack
Auto Release
Release
Soft
Knee
Max.
Comp.
Neg.
Comp.
Compressor
Delay
0-50mS
Level
Detector
Gain
Control
Threshold
Ratio
Gain
Gate
(& Sidechain)
Input
Mode
Gain
Cells
SIGNAL PATH
SIDECHAIN
Summary of Contents for 1212M
Page 1: ...1820 1820 Owner s Manual Owner s Manual ...
Page 8: ...8 E MU 1820M 1820 1212M PCI Digital Audio System ...
Page 54: ...4 The PatchMix DSP Mixer Main Section 54 Creative Professional ...
Page 110: ...5 Effects E MU E Wire VST 110 Creative Professional ...
Page 116: ...6 Using High Sample Rates Overview 116 Creative Professional ...
Page 138: ...7 Appendix Internet References 138 Creative Professional ...