Proel PC260 User Manual
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TIME
Determines how quickly the DEQ filter reacts to signals that reach
the threshold (attack) and how slowly it is restored after signal goes
goes away from the threshold (release) . The table to the left shows
all possible settings and the relative attack and release time . In order
to avoid "pumping" effect on the signal, choose a fast setting for high
frequency EQ and a slow setting for low frequency EQ .
MODE
It determines if the DEQ filter works when the signal is ABOVE the
threshold or when the signal is BELOW the threshold .
SIDECH
Sidechain determines how the detection block analyzes the signal .
In normal mode (NORM) the whole signal is sent to the threshold
detection block . In sidechain mode (SIDE) a filtered signal is sent
to the threshold detection block . The filter applied for the sidechain
is choosen according to the TYPE of filter selected for the signal
equalization (see the table) .
BYPASS
Enable or disable the single DEQ filter .
LEV METER
As show in the block diagram, the level meter receives the signal after the sidechain block, so it shows the signal that controls the
threshold detection block for a specific filter . It's useful for checking your sound program and set an appropriate threshold level .
GAIN METER
The GAIN meter shows the amount of gain / reduction of the filter . Depending on how the filter MODE is set (ABOVE / BELOW) you
can see the filter action while the sound is played .
The example below shows how to use the DEQ for obtaining an automatic loudness effect .
In filters 1 and 3, low and high frequencies are boosted when the signal is BELOW the threshold: this means that the sound is richer
and more defined with a low level signal . Whenever the signal goes above the set theshold, the low and high frequency boost is
reduced or cancelled .
The filter 2 has a cut in the mid-high region that is activated when the signal goes ABOVE the threshold: this means that with a high
level signal the sound is more pleasant and less harsh .
Note that the time setting is decreasing with frequency and that the SIDECHAIN is set to NORMAL for the HF band because, in a typical
audio spectrum there isn't sufficient energy in high frequency range for driving properly a dynamic control .
Time definitions for DEQ cells.
Label
Attack Time (ms)
Release Time (ms)
Fast 1
1
10
Fast 2
4
40
Medium 1
8
80
Medium 2
20
200
Medium 3
40
400
Slow 1
80
800
Slow 2
100
1000
TYPE (signal equalization)
SIDECH: SIDE filter
Low Shelf at freq . f0
Low pass, cut freq . f0
Peaking centered at f0
pass band centered at f0
High Shelf at freq . f0
High pass, cut freq . f0