Access virus os2 Manuale Utente

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VIRUS Owner’s Manual
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chain. When you turn the FILTER BALANCE pot clockwise, Filter 1 is blended out of the signal chain until
at the far right position only Filter 2 is active and audible.
The term used to describe the efficiency of a filter is „slope.“ The unit of measurement is the so-called
filter pole: the more poles a filter has, the greater its slope. 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 pot to
the center position (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 substantially when you set the pot to this position.
Experiment with the diverse FILTER BALANCE positions to get a feel for the different degrees of slope.
Rotate the CUTOFF pot or activate the filter envelope (for both filters!) to hear the filters in action.
The CUTOFF 2 pot is a special feature: It controls the cutoff frequency of the second filter, but is
subordinate to the CUTOFF pot 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 pot to the left
the cutoff frequency level of Filter 2 is increased relatively to Filter 1, when you turn to pot to the right
the cutoff frequency level is decreased relatively. Now when you adjust the CUTOFF pot, you adjust the
cutoff frequency of both filters by the same measure! This feature lets you determine a difference in
values in the filter frequencies (called an offset) via the CUTOFF2 pot which remains constant whenever
you adjust the CUTOFF pot.
Yet another experiment in which you can come up new filtering characteristics that are typical of the
Virus:
Set the FILTER BALANCE pot to the center position (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 SATURATION curve.
Now you can filter this complex signal produced by a combination of the saturation stage and the Filter 1
yet again. Rotate the CUTOFF 2 pot 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 press
the FILT 2 SELECT button and rotate the RESONANCE pot to the desired position. Set the CUTOFF 2
pot to a position to the right of the center position. This configuration can be described as a complex
non-linear filter set up where the cutoff frequency is controlled via the CUTOFF pot. You can dial in a
wide range of sound-shaping option via CUTOFF 2. Also try modifying the resonances of both filters as
well as the SATURATION curve to come up with different filtering characteristics.
Now experiment with the diverse filter modes and listen closely to the effect of the parameters
RESONANCE, ENV AMOUNT and KEY FOLLOW in conjunction with the SELECT button. Please also keep
in mind that the chances of choking a sound off  are substantially greater when you are using both filters:
For instance, if the first filter is used as a low pass with a low cutoff frequency and the second as a high
pass with a high cutoff frequency, the Virus will not generate an audible signal when you set the FILTER
BALANCE pot to the center position (12 o’clock).