Behringer Feedback Destroyer Pro FBQ2496 - Manual (Page 8)

8 FEEDBACK DESTROYER PRO FBQ2496 User Manual
4. FBQ2496 Filters
The FBQ2496 filters can be set up in an extremely narrow-band fashion. This way,
the FBQ2496 changes the way your music sounds to such a minor extent that the
actual change is absolutely negligible and inaudible.
Fig. 4.1: Filter curve of a narrow-band filter
1. Press POWER to turn the unit on. The display shows run (run).
2. Select whether you wish to run your FBQ2496 in stereo or in mono ((13)).
Let us assume that both FEEDBACK DESTROYER PRO channels are coupled
in stereo.
The 20 filters pro channel can be divided up among Single-Shot filters,
automatic filters and parametric filters (fig. 4.2).
◊ The number of all filter types per channel is always 20!
◊ If the number of both fixed and parametric filters is set to zero, your FBQ2496
operates with 20 automatic filters per channel.
Single Shot-
filters
automatic
filters
parametric
filters
Fig. 4.2: Different filter types (shown here in stereo operation)
4.1 Setting up Single-Shot filters
If no Single-Shot filters have been set up, the FBQ2496 looks for critical
frequencies after being powered up, and deploys as many filters as necessary to
combat the problem.
Single-Shot filters can be set up to work with extreme dependability and
comfort. To this end, either use the LEARN or the AUTOLEARN function of
your FBQ2496.
◊ To work with the LEARN or the AUTOLEARN function, the FBQ2496 must
be connected to a PA system.
◊ Using the LEARN or AUTOLEARN functions only makes sense if you are
dealing with PA systems and rooms that are also used for concerts
and recordings.
LEARN mode
1. Briefly press the LEARN button.
The button LED lights up and the LED on the PANIC button blinks. The current
number of Single-Shot filters is shown in the display. (S 0 = no Single-Shot
filter selected, S20 = all filters deployed as Single-Shot filters).
The FBQ2496 immediately starts searching for critical frequencies at
maximum speed and deploys as many Single-Shot filters as necessary
(for this to work, your room has to have a functioning PA system with a
signal fed into it). The number of filters deployed will be increased on a
per-need basis and will be shown in the display.
2. You can use the wheel to change the number of Single-Shot filters
afterwards as well.
3. Press the LEARN button again to exit.
AUTOLEARN mode
This function is useful for automatically setting up Single-Shot filters before the
start of a live performance (“priming” the unit).
1. Keep the LEARN button pressed for longer than one second.
Then, the following happens automatically:
• The button LED blinks.
• All Single-Shot filters and automatic filters are reset.
• A time countdown runs in the display, from 16 seconds to zero
(L16, L15, ... , L 1, L 0).
The FBQ2496 creates impulses with a signal level of -15 dB in order to provoke
feedback. The overall amplification of your FBQ2496 is incrementally increased
from 0 dB to 15 dB). The FEEDBACK DESTROYER PRO detects the critical
frequencies and lowers them in an extremely narrow-band fashion.
2. Critical frequencies are consecutively lowered and stored in the storage slots
of the Single-Shot filters.
3. After the time had run out, the procedure is over. The LED on the LEARN
button is no longer lit and the display shows run.
◊ The frequency of the adjusted Single-Shot filters can not be
manually changed afterwards. However, minor feedback frequency
changes are implemented automatically. Gain adjustment is also
automatically performed in the background, constantly adjusting to
the current conditions.
◊ If a satisfactory setting for the Single-Shot and automatic filters
has been achieved, you can keep this setting by pressing the FREEZE
button. The display shows: -.