Mono Input Channels; Stereo Input Channels - Behringer EURODESK SX3282 User Manual

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EURODESK SX3282 User Manual

3. Mono Input Channels

Each channel comes with a balanced line input on ¼" TRS jack, and an XLR mic
input. Press the Phantom switch (71) at the back panel if required. The mic amp
circuit has an unusually wide gain range (1) from 10 dB to 60 dB, is of extreme
low-noise design, and utilizes high-current conjugate pair vintage transistor
circuitry to deliver an incredibly warm and transparent sound.
When a jack is plugged into the balanced (self-unbalancing) line input, the gain
structure is such that it can match any line level from +10 to -40 dBu. The crucial
operating levels +4 dBu and -10 dBV are clearly and accurately legended ( (1) ).
3.1 Input Level Setting
Channel input level is determined by the GAIN trimpot (1) . Use Solo/PFL (13)
to accurately monitor the channel input on the left/right master output bargraph
meters. This also sends the Solo/PFL-ed signal to the left and right speakers.
Channel Solo (13) has an associated LED (14) .
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For level-setting (as opposed to localized listening) choose to use the
Mono PFL bus rather than the post-fader (post-channel pan) stereo solo
bus (Channel MODE switch (38) not depressed). Solo/PFL never interrupts
the mix at the main recording outputs. It follows that aux sends and
subgroups must also be unaffected, since they contribute directly to
the main mix.
In addition to switchable Solo/PFL metering, a couple of channel LEDs ( (10) / (12) )
illuminate when a signal is present (-20 dB), or if a channel is going into overload.
These LEDs are particularly useful when using extreme EQ settings, or adding a
dynamics processor via an insert.
You do not want the overload light to come on except very intermittently during
a take or a mix. If it does light persistently, reduce input gain (see also the
essential section 8 "Setting up").
3.2 Equalizer
All mono input channels are fitted with a semi-parametric 3-band EQ, plus a
switchable low-cut filter for eliminating unwanted subsonics. The upper (2)
and lower (5) shelving controls have their frequencies fixed at 12 kHz and
80 Hz respectively. The midrange control (3) is semi-parametric with a
peaking response, Q fixed at 2 octaves, sweepable from 100 Hz - 8 kHz ( (4) ).
All three bands have up to 15 dB of cut and boost, with a center detent for
"off". Thirdly, there is a steep high pass (low-cut) filter (6) , slope @ 18 dB/oct,
for reducing floor rumble, breath noise and popping, woolly bottom end etc.
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The combination of shelf boost at 80 Hz together with low-cut at
75 Hz results in a peaking response, useful for adding warmth to
vocals and instruments, and a firm bottom to kick drums and basses,
without losing control of low frequency speaker cones.
3.3 Aux Sends
All eight aux sends (7) are mono and post-EQ. Aux sends 1 & 2 are fixed to be
pre-fader for cueing purposes, while 3 & 4 are fixed post-fader for sending to
effects etc. A shift switch (8) toggles the third pair of aux send potentiometers
between two bus pairs (5 & 6 or 7 & 8). These four aux sends are switchable
pre/post-fader en bloc using the PRE switch (9) .
For almost all FX send purposes, you will want aux sends to be post-fader, so that
when a fader level is adjusted, any reverb send from that channel follows the
fader. Otherwise, when the fader is pulled down, the reverb from that channel
would still be audible. For cueing purposes, aux sends will usually be set
pre-fader, i.e. independent of the channel fader (depress PRE switch (9) for aux
sends 5/6/7/8).
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Most reverbs etc. internally sum up the left and right inputs. The very
few that do not may be driven in true stereo by using 2 aux sends.
There is +15 dB of gain on every aux send. Such a high boost is usually
only appropriate where the channel fader is set around -15 dB or lower.
Here, an almost exclusively wet signal will be heard. In most consoles, such a
wet mix requires the use of a pre setting for the channel aux send, losing fader
control. With the SX3282 you can have a virtually wet mix with fader control.
Channels may be altered for pre-EQ aux sends (see section 13 "Modifications").
3.4 Routing & Muting
Routing means selecting which bus you want a channel to address. There are
five stereo buses in the SX3282 (plus a stereo solo bus). Main mix and the four
subgroup pairs are selected by five assign switches (18) . Solo/PFL we encountered
in the section on input level setting (3.1).
Channel PAN (11) positions the output of the channel in the stereo field.
Its constant-power design ensures there are no level discrepancies whether a
signal is hard-panned, center-stage, or somewhere in-between. Such pin-point
accuracy will be a revelation if you have been working on consoles with lower
quality circuits.
All stereo buses follow channel Pan. Usually, only one of L-R, 1-2, 3-4 etc. will be
selected for a particular channel.
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An exception to this rule is when laying down voice takes. It is often
convenient to have the mic channel(s) routed to all potential take
tracks simultaneously, since you are often dropping in quickly between
four or more tracks. It means one less button to press each time you
switch tracks.
Level to the group and main left and right buses is ultimately determined by the
channel fader (17) . This is designed to give a smooth logarithmic taper of a type
more usually associated with megabuck consoles. The low level performance
particularly is far smoother than that of a "normal budget" fader.
The mute button (15) , like that for Solo (13) is ergonomically placed immediately
above the channel fader, and has an associated LED (16) for excellent visual status
indication of this much-used feature. Engaging mute is equivalent to setting a
fader level of minus infinity. It follows that pre-fader aux sends are unaffected by
application of mute.

4. Stereo Input Channels

Each stereo channel comes with two line level inputs on ¼" jacks,
for left and right signals. When only the left input is connected,
the channel operates in mono.
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This feature is disabled, if the inputs and outputs of the SX3282 are
wired permanently to a patchbay (see section 9 "Patchbay").
Channel input sensitivity is variable between -20 and +20 dB by adjusting
GAIN (1) , enabling a perfect match with all common line-level sources including
multitrack tape outputs, MIDI and other electronic instruments and effects units,
all of which are normally designed to operate at either +4 dBu or -10 dBV.
4.1 Input Level Setting
This is exactly as for a mono channel (see section 3.1).
4.2 Equalizer
All stereo input channels are fitted with four-band, fixed-frequency EQ.
Bands 1 and 4 are shelving, while bands 2 and 3 have a peaking response,
with their Q set at 2 octaves.
The upper (2) and lower (5) shelving controls have their turnover frequencies
fixed at 12 kHz and 80 Hz, whereas the midrange controls (53) and (52) have their
bell center frequencies set at 8 kHz and 800 Hz.
All bands have up to 15 dB of cut and boost, with a center detent for "off".