Access virus os4 Manual De Usuario

CHAPTER 

4

Introduction

You can continue modifying the 
sound by reducing the symmetri-
cal width of the pulse wave. In the 
Virus, you can execute this sound-
shaping measure via the WAVE 
SEL/PW (PW = pulse width) pot, 
PROVIDED THE SHAPE POT IS SET TO 

 (LATER THAN 

12 O’CLOCK). Rotate the WAVE SEL/
PW pot slowly from the left to the 
right and leave the SHAPE pot at 
the far right position. You can hear 
how the treble content of the 
sound increases while the sound 
becomes ever thinner. At the far 
right position, the signal is no 
longer audible because the pulse 
width is equivalent to 0% and con-
sequently the wave no longer 
oscillates.

Starting at the center position (12 
o’clock) indicated by the sawtooth, 
turn the SHAPE pot counter-clock-
wise towards the left. You can hear 
how the overtones are increasingly 
mixed out of the signal until you 
can only hear the root note. This 
sound is produced by a so-called 
sine wave, one of 64 other wave-
shapes that you have at your dis-
posal for sound generation 
purposes. These waveshapes can 

also be activated via WAVE SEL/PW 
(WAVE SEL: Wave Select), PRO-
VIDED THE SHAPE POT IS SET TO A 

 (EARLIER THAN 12 

O’CLOCK). Regardless of the cur-
rent SHAPE setting, you can also 
select a wave in the EDIT menu 
under OSCILLATOR 1 WAVE.

Go ahead and check out the differ-
ent waveshapes. The second of the 
64 waves is a triangle wave, the 
remainder of the waveshapes are 
each a unique tonal blend. After 
you have familiarized yourself with 
this raw material, experiment with 
the parameters of the FILTERS and 
AMPLIFIER

 sections you have dealt 

with thus far (don’t forget about 
SATURATION

 and the correspond-

ing function of the OSC VOL pot), 
to get a feel for how the diverse 
waveshapes respond to filtering, 
saturation

 and amplifier modifi-

cations.