SoundCraft Spirit SX, Manual To Mixing

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threshold, but an expander works like an automatic mixing
engineer who pulls down the signal when the signal falls
below the threshold; the more it falls below the threshold -
the more he pulls down the fader.
Expanders are most often use in Studio recording to
provide the best mix signal to noise ratio when producing
final masters.
Compressor/Limiters
A compressor reduces the difference between the loudest
and quietest parts of a performance. It works on a threshold
system where signals exceeding the threshold are processed
and those falling below it pass through unchanged. When a
signal exceeds the threshold the compressor automatically
reduces the gain. How much gain reduction is applied
depends on the ‘compression ratio’ which on most
compressors is variable: the higher the ratio, the stronger
the compression. Very high ratios cause the compressor to
act as a limiter where the input signal is prevented from
ever exceeding the threshold.
Compressors are the most commonly used processor and
are particularly popular for maintaining constant vocal and
bass guitar levels live and in the studio. This is because, out
of all instruments, singers tend to vary their levels the most.
Compressors help to achieve the much sought-after tight,
"punchy" sound.
Setting up a Signal Processor
• Connect your processor to the relevant mixer insert jack
(mono, group or mix insert), using a insert ‘Y’ lead.
Refer to section 7 for wiring information
• Set your processor to unity gain (x1), i.e. no additional
gain.
• Make your adjustments on your signal processor
• Beware that your processor settings may alter your mixer
input output levels. Re-adjust levels to ‘0’ on meters, if
necessary.
NB: Remember a signal processor can be used in a channel to
control one audio source, in a group to control a number of
audio sources, or to control the entire mix.
F. Creating a Foldback/
Monitor Mix
Performers usually require their own mix independent from
the main/engineer’s mix. This is because to achieve the
optimum performance they need to hear themselves above
other voices or instruments. This performer’s mix is known
as a foldback/monitor mix.
The procedure is as follows;
• Set the pre-fade aux to maximum on the relevant
performers input channel.
• Select AFL on your aux master.
• Set aux master level so meters read ‘0’.
• Create a foldback mix for the performer by setting the
pre-fade aux levels on the other performer’s input
channels.
• Release aux master AFL.
NB: It is typical that the performers’ own vocals/instruments will be
two thirds louder than any other sources in their own monitor
mix.
Each performer may require a separate monitor
mix/auxiliary output.
NOTE: Pre-fade rather than post-fade auxiliaries must be used.
This is because they are independent of the input faders. If post-
fade auxiliaries are used, then foldback mix levels will alter with
every input fader change made by the FOH engineer. This will
annoy the band and may lead to feedback which can damage
speakers and headphones.
Now that you know how to connect and set up
different elements of your system let’s look at some
real-world examples of systems in use.
SECTION 3: Mixing T
echniques
16
FIG. 3.15
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