ACCESS VIRUS RACK
185
Oscillators
OSCILLATORS
Pulse Width Modulation
Pulse width modulation is a very effec-
tive method for producing beat oscilla-
tions without having to resort to several
detuned oscillators.
Dial OSC BALANCE to the far left so that
only OSC1 is audible, then select the
waveform Pulse for this oscillator (OSC1
Shape to the right). Slowly turn the Pulse
Width (PW) knob back and forth. As you
change its pulse width, you’ll hear move-
ment in the sound itself. When its pulse
width remains fixed, the sound will
remain static. This to-and-fro pulse width
modulation can be automated by means
of an LFO. Select PWM for LFO1 Amount
and set a relatively high modulation
amount. You can vary the intensity of
the modulation via LFO Rate.
Now when you play different sounds,
you’ll will find that the intensity of the
modulation is considerably greater with
low-frequency sounds than it is with
higher-frequency sounds. This is due to
the fact that the LFO frequency does not
follow the pitch. You can compensate for
this effect by activating and adjusting
the function LFO1 KEYFOLLOW. When
you set LFO1 KEYFOLLOW to a value of
127, the LFO rate will follow whatever
pitch you play precisely (in octaves).
To come up with a fatter sound, you
should also dial in the second oscillator
(set OSC BALANCE to the center posi-
tion) and use DETUNE to do just that to
its pitch (relative to the first oscillator).
Next to LFO1, LFO3 is also able to gener-
ate pulse width modulation. However,
unlike LFO1, LFO3’s modulation algo-
rithm was tweaked specifically to deliver
what we consider hip pulse width modu-
lations. Note that LFO3 PWM often deliv-
ers smoother results, particular a softer,
tighter sound for pads. Another advan-
tage of LFO3 is that it frees up LFO1 so
that you can use it for other sonic chores.
By the way, KEYFOLLOW should also be
activated for LFO3.
Summary of Contents for VIRUS C SERIES
Page 1: ......
Page 3: ...Table Of Contents ...
Page 7: ...ACCESS VIRUS RACK 5 ...
Page 11: ...ACCESS VIRUS RACK 9 ...
Page 15: ...Introduction ...
Page 33: ...ACCESS VIRUS RACK 31 The Second Filter ...
Page 35: ...ACCESS VIRUS RACK 33 Filter Routing Her is the filter routings capabilities of the Virus ...
Page 54: ...52 CHAPTER 4 Introduction ...
Page 55: ...Concept and Operation ...
Page 60: ...58 CHAPTER 5 Concept and Operation ...
Page 61: ...Operation ...
Page 67: ...All About The Memory ...
Page 70: ...68 CHAPTER 7 All About The Memory ...
Page 71: ...Modmatrix And Definables ...
Page 75: ...Master Clock And Midi Clock ...
Page 77: ...The Effects Section ...
Page 79: ...Audio Inputs ...
Page 83: ...Audio Routing ...
Page 85: ...Categories ...
Page 87: ...Random Patch Generator ...
Page 90: ...88 CHAPTER 14 Random Patch Generator ...
Page 91: ...Additional Functions ...
Page 94: ...92 CHAPTER 15 Additional Functions ...
Page 95: ...The Parameters ...
Page 132: ...130 CHAPTER 16 The Parameters ...
Page 163: ...The Vocoder ...
Page 169: ...The Virus and Sequencers ...
Page 173: ...ACCESS VIRUS RACK 171 Organizational Information ...
Page 180: ...178 CHAPTER 18 The Virus and Sequencers ...
Page 181: ...Tips Tricks Words Of Wisdom ...
Page 201: ...ACCESS VIRUS RACK 199 MIDI ...
Page 204: ...202 CHAPTER 19 Tips Tricks Words Of Wisdom ...
Page 205: ...Appendix ...
Page 215: ...ACCESS VIRUS RACK 213 FCC Information U S A ...
Page 217: ...ACCESS VIRUS RACK 215 FCC Information CANADA ...
Page 219: ...ACCESS VIRUS RACK 217 Other Standards Rest of World ...
Page 223: ...ACCESS VIRUS RACK 221 Garantie Bestimmung ...
Page 225: ...ACCESS VIRUS RACK 223 Warranty ...
Page 226: ...224 CHAPTER 20 Appendix ...
Page 227: ...ACCESS VIRUS RACK 225 Warranty ...