19
5.4.1 Recalling programs
After power-up, the FEEDBACK DESTROYERs display reads the number of the preset last used. The jog
wheel allows you to conveniently select the preset of your choice. Turn the rotary control to the left to step
through the programs in descending order. Turn it to the right to increment the programs. The default preset
is located in front of the first program.
+
Please note that the FEEDBACK DESTROYER generally activates the newly selected presets only
after about one second, which is indicated by a dot in the lower right corner of the display. After loading
the data, the FEEDBACK DESTROYER enables the preset and the dot disappears. This brief interruption
avoids the direct activation of every preset, as you scroll through the preset list with the jog wheel.
Otherwise, incomplete "parameter remnants" of presets could reach the audio outputs of the FEEDBACK
DESTROYER, with possibly disastrous consequences, especially when using a high-power P.A. system.
Thus, the FEEDBACK DESTROYER makes sure that no "unwanted" programs are loaded
unintentionally. Additionally, you can rotate the jog wheel at high speed and still have the time to
specifically select the preset of your choice, instead of any of its "neighbors".
5.4.2 Choice of mode
Each filter mode has a letter assigned to it, which appears in the display after pressing the FILTER MODE
key. The following display messages can be recognized:
Display
Mode of operation
O
Off
P
Parametric EQ
A
Auto
S
Single Shot
L
Locked (S)
Table 5.1: FEEDBACK DESTROYER operating modes
To change the filter mode, you first have to press the FILTER SELECT key to specify the number of the filter
(1 to 12) with the jog wheel. Using the ENGINE keys you can not only select the left or right channel, but also
both ones at the same time. Then you can choose the filter mode by simply pressing the FILTER MODE key
and turning the jog wheel. The display message “L” (locked) informs you that a filter from the Single-Shot
mode is already suppressing a feedback. You can unlock such a filter by switching it back to single mode. As
soon as a new feedback will be found, the FEEDBACK DESTROYER switches the filter from the old fre-
quency to the new one. If you leave the Auto or Single-Shot mode and enter the Parametric mode, the filter
keeps all parameter settings.
In order to avoid an inadvertent changeover, the filter mode selection takes place after a period of approxi-
mately one second. This is indicated by a dot in the lower right corner of the display. To accelerate this
process simply press any other key.
By pressing and keeping the FILTER MODE and the GAIN key for about 2 seconds you can adjust the
feedback threshold within a range of -3 dB to -9 dB.
5.4.3 Editing filter parameters
To change filter settings, the filter has to situate in Parametric EQ mode. In this case you can adapt the center
frequency by pressing the FREQUENCY key. Depending on the frequency, either the “Hz” or “kHz” indicator
to the right of the display lights up. If you want to lift the frequency to e.g. 2700 Hz turn the jog wheel until the
ISO frequency (2.5 kHz, see table 1.2 standard ISO frequencies) closest to this value appears in the display
and the “kHz” indicator lights up. The FINE key allows you to fine tune the chosen standard ISO frequency
within a tuning range of 1/3 octave (in 1/60-octave steps). The mathematic proportion between the displayed
value and the absolute frequency, and an easy guide to quickly find the desired frequency is available in
chapter 7 (frequency chart). The bandwidth of the filter can be adjusted by selecting the BANDWIDTH key.
The adjustable bandwidth ranges from 2 octaves down to 1/60 octave. By pressing the GAIN key it is possi-
ble to set the desired boost or cut of the selected frequency. A “+” signals that the level is being increased and
a “-” signals a decreasement.
5. OPERATION
