The Second Filter - Access Virus Rack User Manual

28 CHAPTER 4
Introduction

THE SECOND FILTER

You probably noticed that by a adding a
bit of saturation to the signal you can
come up with a pretty heavy, aggressive
sound - especially with a low filter fre-
quency level and high resonance. You're
probably thinking these types of sounds
could do with some more filtering. We
had the same idea, which is one of the
reasons why we equipped the Virus with
another filter per voice.
The technical design of this second filter
is identical to the first, so we won't dis-
cuss it in as much detail as we did the
first filter. However, there are few differ-
ences in how you handle the second fil-
ter:
Only two parameters of the Virus are
allocated exclusively to Filter-2: CUTOFF
2 and FILT 2 MODE.
The RESONANCE, ENV AMOUNT and
KEY FOLLOW parameters can be allo-
cated to either of the two filters or both
simultaneously. Use the FILTER SELECT
menu in the FILTERS section to select the
desired operating mode. For instance, if
you choose FILT2, then the values you set
with RESONANCE, ENV AMOUNT and
KEY FOLLOW apply exclusively to Filter-
2. The corresponding parameters of Fil-
ter 1 remain unaffected. On the other
hand, if you choose FILT1+2, the values
that you dial in apply by the same mea-
sure to Filters 1 and 2.
In the sound program we are using for
our experiments, both filters are
selected, so that all adjustments to the
given parameters affect both filters.
However, you have yet to actually hear
the effect of Filter-2 on the signal
because it is mixed out of the audible
signal path of the Virus.
Before we get started with our next
experiment, deactivate SATURATION, set
the ENV AMOUNT of the filter envelope
to zero and set CUTOFF 2 to the center
position so that Filter-2 always has the
same cutoff frequency as Filter-1 (we'll
explain CUTOFF 2 a bit later). Set CUT-
OFF to a medium or middle value and
turn the RESONANCE encoder counter-
clockwise to the far left to achieve a rela-
tively muddy sound.
Now locate the FILTER BALANCE param-
eter in the FILT menu and rotate it from
the left to the right. You will note the
sound becomes muddier as you turn the
encoder towards the center position and
that the sound is somewhat brighter at
the far right of the control range then at
the far left.
The reason for this effect is that when
you turn the FILTER BALANCE to the far
left, only Filter-1 is audible. When you
rotate the parameter to the right, Filter-
2 is blended in so that it follows Filter-1
in the signal chain. When you turn the
FILTER BALANCE clockwise, Filter-1 is