The Peak Limiter Section; The Rear Panel Control Elements; Examples Of Sidechain Applications; Eliminating Interference - Behringer Composer PRO-XL MDX2600 User Manual

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MULTICOM PRO-XL MDX4600/PRO-XL MDX2600/AUTOCOM PRO-XL MDX1600 User Manual
(26) DE-ESSER LEVEL (MDX2600). The LED chain reads the current attenuation
within a range from +3 to +12 dB.
(27) MALE switch. This switch adapts the de-esser to the male (switch pressed)
or female registers (not pressed).
(28) IN/OUT switch. Switches the de-esser on and off.

2.5 The peak limiter section

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Fig. 2.6: Peak limiter section control elements
(29) The peak limiter limits the signal to an adjustable level. When the LIMITER
control is turned fully to the right, the limiter is switched off. Owing to
its extremely fast "zero" attack, this circuit is capable of limiting signal
peaks without any overshoot. If the signal is limited for more than 20 ms,
the overall gain is reduced for about 1 s to avoid strong and thus audible
limiter effects.
◊
If you wish to use the peak limiter as a protecting device, the LIMITER
control and the OUTPUT control in the compressor section should be set
so that the peak limiter responds only rarely or never at all. It should
be triggered by peak signals only. To achieve creative sound effects,
on the other hand, you can also intentionally drive the peak limiter into
this peak limiting range.
(30) The LIMIT LED lights up as soon as the limiter is on.

2.6 The rear panel control elements

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Fig. 2.7: Power supply and fuse
(31) FUSE HOLDER/VOLTAGE SELECTOR. Before connecting the unit to the
mains, ensure that the voltage setting matches your local voltage. A blown
fuse should only be replaced by a fuse of the same type and rating.
Please refer to chapter 6 "Specifications" for details.
MAINS CONNECTION. Use the power cord supplied with the unit to connect
it to the mains. Please note the instruc-tions given in chapter 5 "Installation".
(32) OUTPUTS. These are the audio outputs of your dynamics processor. The two
matching 1/4" TRS and XLR connectors are wired in parallel and balanced.
Of course, unbalanced cables can be connected here as well.
(33) OPERATING LEVEL switch. This switch can be used to adapt the COMPOSER
PRO-XL, AUTOCOM PRO-XL or MULTICOM PRO-XL to various operating levels,
i.e. to toggle between home recording level (-10 dBV) and studio level
(+4 dBu). The level meters will be referenced automatically to the nominal
level adjusted, so that the compressor works in its optimum operating range.
(32) (33) (34)
MDX4600
(32) (33)
MDX2600/MDX1600
Fig. 2.8: Rear panel connectors and switches
(34) INPUTS. These are the audio inputs. They are also on balanced 1/4" TRS and
XLR connectors.
(35) (36)
Fig. 2.9: SIDECHAIN connectors
(35) SIDECHAIN SEND. This is the unbalanced sidechain output, which allows
you to route the audio signal to other devices for external processing.
(36) SIDECHAIN RETURN. The sidechain input allows you to use an external
signal or the processed (e.g. with an equalizer) audio signal routed from the
SIDECHAIN SEND jack to control your COMPOSER PRO-XL or AUTOCOM PRO-XL.
3. Examples of Sidechain
Applications
A very common type of application is to make the compressor threshold
frequency-dependent by inserting a graphic or parametric equalizer into the
side-chain path. To be able to keep the threshold setting on the MDX1600 or
MDX2600, unwanted frequencies should be cut with an inserted equalizer,
without affecting the levels of selected frequencies. For example, to control the
compressor from a narrow-band midrange frequency band, we recommend
reducing the bass and treble controls on the inserted EQ, while leaving the
midrange control set to 0 dB.

3.1 Eliminating interference

Insert an equalizer into the sidechain control path in the following order:
SIDECHAIN SEND - equalizer - SIDECHAIN RETURN. Turn the THRESHOLD control
to the left until the GAIN REDUCTION meter reads a clearly noticeable gain
reduction. Now the equalizer must be set so that all frequencies are reduced in
level, except for the interference frequencies. Thus, the interference signal will
trigger the compression.
Using this technique you can, for example, reduce the dynamics of a bass
drum that is too loud in an existing recording. Simply use an equalizer to cut
all frequencies above 150 Hz, so that the compression will be triggered by the
individual beats of the bass drum.
◊
To monitor the equalizer setting, press the SC MON switch to isolate
and play back the processed signal.
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