Access Virus Rack User Manual page 31

blended out of the signal chain until at
the far right position only Filter-2 is
active and audible.
Each filter in the Virus normally features
2 poles. However in the FILTER ROUTING
operating mode SER 6, Filter-1 operates
with 4 poles, so the signal patched
through Filter-1 (FILTER BALANCE to the
far left) is trimmed more drastically than
when it is routed through Filter-2 (FILTER
BALANCE to the far right). When you set
the FILTER BALANCE to the center posi-
tion (12 o'clock) - as we mentioned
before - the two filters are routed in
series, which means they respond as if
they were a single filter with 6 poles and
consequently a great deal of slope. This
is why the input signal is trimmed sub-
stantially when you set the parameter to
this position.
Experiment with the diverse FILTER BAL-
ANCE values to get a feel for the differ-
ent degrees of slope. Rotate the CUTOFF
encoder or activate the filter envelope
(for both filters!) to hear the filters in
action.
The CUTOFF 2 parameter is a special fea-
ture: It controls the cutoff frequency of
the second filter, but is subordinate to
the CUTOFF encoder located above it. In
other words, at the center position (12
o'clock) the manually selected frequency
of Filter-2 is identical to that of Filter-1.
When you rotate the encoder to the left
the cutoff frequency level of Filter-2 is
increased relatively to Filter-1, when you
turn to encoder to the right the cutoff
frequency level is decreased relatively.
Now when you adjust the CUTOFF, you
adjust the cutoff frequency of both fil-
ters by the same measure! This feature
lets you determine a difference in values
in the filter frequencies (called an offset)
via the CUTOFF2 encoder which remains
constant whenever you adjust the CUT-
OFF encoder.
Yet another experiment in which you
can come up new filtering characteristics
that are typical of the Virus:
Set FILTER BALANCE to the center posi-
tion (12 o'clock) and CUTOFF 2 to the
maximum level. The FILTER ROUTING
operating mode must remain SER 6. Set
CUTOFF and RESONANCE to a middle
value and select a clearly audible SATU-
RATION curve.
Now you can filter this complex signal
produced by a combination of the satu-
ration stage and the Filter-1 yet again.
Rotate the CUTOFF 2 encoder slowly
towards the center position (12 o'clock).
You can hear how Filter-2 gradually
modifies the distorted signal. You can set
a RESONANCE value for Filter-2 if you
choose FILT 2 in the FILTERS SELECT
menu and rotate the RESONANCE
encoder to the desired position. Set the
CUTOFF 2 encoder to a position to the
right of the center position. This configu-
ration can be described as a complex
non-linear filter set up where the cutoff
frequency is controlled via the CUTOFF
encoder. You can dial in a wide range of
sound-shaping option via CUTOFF 2. Also
try modifying the resonances of both fil-
ters as well as the SATURATION curve to
come up with different filtering charac-
teristics.
ACCESS VIRUS RACK 29
The Second Filter