User`s manual

AEQ FORUM - DIGITAL AUDIO MIXER FOR BROADCAST APPLICATIONS
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reduced to half at the output. The highest ratio available is 50:1, which will be used to
implement signal limiters. The limiter must reduce all signals exceeding a certain level
to that level.
• ATT (Attack Time): This is the time it takes the compressor to react to an increase in the
input signal. The shorter this time, the more sensitive the compressor will be to pulse
signals, and the it will act on this type of signals. With a long attack time, the
compressor will not respond so well to pulse changes in the input signal.
• G (Gain): This enables you to apply a general g to the signal. This entails a general
increase of the signal level, which will be especially noted at low input levels that are
under the threshold set. A general increase in the level of the signal may generate
saturation at the output, even when the signal is being limited.
• REL (Release Time): This is the maintenance time during which the compressor keeps
acting, even when the level of the input signal has fallen below the threshold. A long
release time will maintain uniform compression, even when there are quick level
fluctuations in the signal. A short time will enable the compressor to adapt more quickly
to pulse fluctuations in the signal.
NOTE: To correctly set a limiter, a threshold between 0 and +22 dB should be selected, with a
compression ratio of 50:1 and a gain of 0 dB.
The COMP contextual key enables you to activate the compressor whose parameters are
shown at that time on the screen. The activation of the compressor is confirmed by the
activation of the LED of the contextual key and the LED associated with DYN in the active
process indicator section of the selected mixer channel. See section 2.1.1.5. Active Process
Indicators, of this manual.
Important Note: The dynamics process, and especially the compressor / limiter, requires either
extensive experience or caution and time to check, while off the air, the result obtained on the
signal. Without these precautions, you may generate sound effects that can be perceived as
dirty sound, lack of definition, distortion and other defects in general.
By pressing the NGATE contextual key you will access the screen dedicated to the control and
configuration of the noise gate for the input channel in question.
Noise gate
A noise gate is a dynamics processor that lets signals through whose level exceeds a certain
threshold, strongly attenuating the signal levels below that threshold and thus muting noise. It
enables its user to eliminate extraneous noise from a signal source, whether it is background
noise in the studio—in the case of a microphone—or the background noise generated by a
playback device—for example, a tape.
From top to bottom and left to right, the information shown in the noise gate configuration and
control screen (the description of the fields is identical to the compressor / limiter field
description) is as follows:
• ATT (Attack time).
• THR (Threshold).
• REL (Release time).
• R (Range).
• HOL (Hold time).