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CHAPTER 
4
Introduction
THE FIRST OSCILLATOR
To this point, we have turned our 
attention exclusively to sound-
shaping functions and have always 
started with the same basic mate-
rial: a so-called sawtooth wave. 
This waveshape is especially well-
suited as a neutral starting point 
as it contains all of the so-called 
natural scale of overtones, which 
give the filter plenty of quality 
material to work with.
The filters, with the exception of a 
notch filter or band stop (BS), trim 
the far reaches of the tonal spec-
trum, so for instance a signal 
sounds muddier after it has been 
routed through a low pass filter. 
You can well imagine that this type 
of sound modification is substan-
tial but insufficient for shaping 
more subtle differences in tone. 
For instance the tone of a trumpet 
differs significantly from that of a 
saxophone even though no one 
would seriously claim that either 
of the instruments has a muddier 
tone than the other.
What you need is a sound-shaping 
option for the portion of  a signal 
that a filter allows to pass. And of 
course you also need a tool for 
determining the pitch of a signal. 
In synthesizers, both of these tasks 
are executed by oscillators. They 
oscillate at a variable pitch that 
can be modulated and they also 
generate different waveshapes 
which give the filters a wider vari-
ety of material to work with.
The Virus is equipped with two 
main oscillators and a so-called 
suboscillator. We will first take a 
look at Oscillator 1, which is the 
oscillator you have already heard 
in action during your experiments 
thus far. 
Dial in the same basic sound that 
you started with at the very begin-
ning. Now modify the amplifier 
envelope so you are working with 
a less grating sound, but hold back 
on any other filter or saturation 
modifications so you can hear the 
purest oscillator signal possible.
Locate the section labeled “1”, it is 
bordered off in a separate area at 
the far left of the section labeled 
OSCILLATORS
. No check out the two