Behringer high-precision digital 24-bit/96 kHz EQ/RTA mastering processor DEQ2496 - Manual (Page 16)

16 ULTRACURVE PRO DEQ2496 User Manual
4.2 Equalizer in the monitor path
The use of the ULTRACURVE PRO in the monitor path follows the same
basic rules as the sum-signal equalizer application described above.
Additionally, the DEQ2496 offers a few features that are particularly useful
for monitoring purposes.
The Feedback Destroyer helps you identify and eliminate feedback frequencies
during sound check. Once a specific feedback frequency has been found, it can be
eliminated by assigning the corresponding filter to it in SNGL mode. If hand-held
(i.e. wireless) microphones are used, the acoustic conditions will be changing
all the time. In this case, it is useful to set the Feedback Destroyer filters to
automatic search mode (AUTO). The Feedback Destroyer is suited only for those
signal paths that carry heavily modulated signals only (speech, vocals, drums).
In principle, there is no way to distinguish long-sustaining sine tones produced
for example by a synthesizer or flute from feedback. Here, the result would be the
unwanted elimination of such sounds. If all automatic filters are already in use
suppressing feedback, and a new feedback frequency is found, the first filter used
will be released and set to the new frequency. The Feedback Destroyer can work
no miracles, but it can increase the feedback immunity of the audio system by a
few dBs. Whenever it responds, you should consider this a warning to reduce the
volume level on stage.
Basically, the on-stage volume level should be kept as low as possible, because:
1. it will be easier on your hearing,
2. there are less feedback problems, and
3. it’s easier to achieve a good P.A. sound.
Often, the volume of the monitor speakers is raised as a concert goes on.
Use breaks and pauses to reduce all monitor paths by about 3 dB. The musicians
will not or hardly hear that the volume has been reduced, because during a break
their hearing can relax a bit. This gives you valuable headroom in your system.
If you use certain speaker types on a regular basis, you can save standard settings
on your equalizer, which have proven useful in practice (e.g. for 15" wedge or
drum-fill speakers). Extremely low frequencies are usually faded out completely
to avoid a “muddy” sound on stage caused by low-frequency feedback.
Monitoring mixing
console
AFL Output
Outputs 1 to 8
RTA Input
Sidefill L
Sidefill R
Sidefill Drums
Keyboard Fill
Wedge 1
Wedge 2
Wedge 3
Wedge 4
Fig. 4.3: Several ULTRACURVE PROs in a monitor system
Figure 4.3 shows an example of using several ULTRACURVE PROs in a 8-way
monitor system. The AFL output of the monitor console (usually feeding the
control speaker at the monitor console) can alternatively be connected via the
RTA/MIC input. On the DEQ2496, select the RTA input in the RTA menu to display
the signal of the currently active monitor path.
4.3 Using the ULTRACURVE PRO in the studio
The number of possible uses for your DEQ2496 in a studio environment is endless.
Your imagination is the only limit. Here are just a few examples:
As an equalizer for the monitor speakers: apart from the usual graphic
equalization (GEQ) the parametric filters (PEQ) can be used efficiently to suppress
narrow-band room resonance. What is more, the DEQ2496 functions as an A/D
and D/A converter for the conversion of analog to digital, and vice versa.
As a mastering equalizer: Owing to the stereo link function all settings on the
graphic equalizer must be made only once. Here, too, the additional parametric
filters can be used effectively for fine-dosed equalization. Use the AES/EBU
inputs/outputs (optional) for sound processing purely in the digital domain.
For general sound shaping: The option to change programs via MIDI and modify
all parameters via MIDI controllers makes the ULTRACURVE PRO a particularly
flexible tool if combined with a MIDI sequencer. For example, this allows you to
change settings during mix-down and still have them reproducible all the time.
4.4 Using the ULTRACURVE PRO as a delay unit
Apart from the applications described in chapter 4.1, it also happens that speaker
stacks must be set up at a larger distance from the stage to produce some direct
radiation at remote positions. In order to make up for the run-time differences
between the on-stage speakers and the remote stacks, the latter must be
provided with an electronically delayed signal. Usually, special delay lines are
used for this, however, not so with the DEQ2496, because it already includes a
signal-delay option. This function can be operated as conveniently as on any
dedicated device. The delay setting is stored with a program, and by using
the MAIN and AUX outputs you need only one DEQ2496 to set up a delay line:
simply delay one of the output signals and send it to the remote speaker stacks.
XENYX 2222FX
ULTRACURVE PRO
DEQ2496
Main output L + R Aux output L + R
(Delay Line)
Stereo output L + R
Fig. 4.4: Run-time correction in a sound reinforcement system using the ULTRACURVE PRO