The Mixer Section; The Lfos - Access Virus Rack XL User Manual

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CHAPTER 5
Introduction
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THE MIXER SECTION

You have already come across two parameters
of the MIXER section: OSC BAL determines the
mix ratio between Oscillators 1 and 2; in the left
half of its control range, OSC VOL determines
the master volume of the oscillator mix. In the
right half of the control range from the center
position to the far right, OSC VOL increases the
saturation intensity when a SATURATION curve
has been activated.
Now we'll take a closer look at the SUB OSC
parameter: It controls the volume of the third
oscillator, the so-called SubOscillator, which al-
ways operates an octave below Oscillator 1.
The SubOscillator is mixed to the Oscillator 1
and 2 master mix signal as determined by the
OSC BAL parameter. The master volume of the
composite mix is controlled by the OSC VOL
parameter. The only other parameter available
for the SubOscillator is accessible via the OS-
CILLATOR EDIT menu where you have the op-
tion of selecting a triangle or pulse waveshape
(SUB OSCILLATOR WAVE SQUARE/TRIAN-
GLE).
Another voice-internal signal source of the Virus
is the Noise Generator (NOISE Volume). Please
keep in mind that the level of the Noise Genera-
tor is not subject to the master volume control-
led by the OSC VOL parameter. In other words,
it is audible even when OSC VOL is set to zero.
The VIRUS' ring modulator is a new sound
source. The output of the two oscillators is mul-
tiplied to create interesting sounds with rich en-
When you first started this series of experi-
ments with sounds, we promised that many of
the functions the Virus can be "programmed"
so that they are executed automatically. You
have already learned how to control the volume
harmonic overtones. These overtones are highly
dependent on the frequency coherence of both
oscillators and it's waveforms. The frequency
coherence can be changed, for instance use
the OSC2 SEMITONE parameter. To blend in
the ring modulator use EDIT: RINGMODULA-
TOR VOLUME (in OSCILLATOR EDIT Menu). If
the RINGMODULATOR VOLUME is zero, the
ring modulator is switched off. OSC VOL does
not affect the ring modulator level (or indeed the
noise volume). Therefore the original oscillator
signal can be leveled independently of the ring
modulator. Be sure to check out what the ring
modulator does when you select a sine wave
for Oscillator 1 and 2.
Now we can go on and solve the mysteries of
the signal flow as determined by the FILTER
ROUTING operating mode SPLIT: Here Oscilla-
tor 1 and the SubOscillator are routed to Filter-
1, whereas Oscillator 2 and the Noise Generator
are routed to Filter-2. Although the sound
sources are split into two signal paths, you can
still control the volume levels of the different el-
ements as well as OSC VOL in the usual man-
ner.
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THE LFOS

and cutoff frequencies of both filters as well as
the pitch and intensity of the frequency modula-
tion of Oscillator 2 via "preprogrammed" enve-
lopes. These options are great, but you have
already encountered a number of functions