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VIRUS POWERCORE MANUAL 27
GETTING STARTED
Getting Started
An Introduction to Viral Synthesis
For the benefit of synthesis newbies, we will first discuss some of the basic concepts to
help you get an idea of what this is all about. The Virus PowerCore is based on
'subtrac-
tive' synthesis
, which means that the sound begins life in the
oscillator
section as har-
monically rich as it's going to get, then certain elements are removed via the
fi lter
section and what's left is sculpted into the desired shape by the
ampli fi er
section. Of
course the Virus PowerCore is a lot more complex than this! What follows is an overview
of the main stages that constitute any Virus sound or 'patch'.
Oscillators
This is where life begins for a Virus PowerCore
sound. An
oscillator generates a basic
wave-
form
, which, if left untreated, will sound as a
continuous tone for as long as a key is held.
Different waveforms contain different amounts of
harmonics
- it's these that give the
waveform it's timbre, or tonal character. For instance:
> Saw:
Saw waveforms contain both odd and even harmonics, resulting in a very bright
and harsh tone.
> Pulse:
Pulse waveforms (also known as a square wave) contains only the odd har-
monics, which results in a bright, but somewhat 'hollow' tone.
> Sine:
Sine waveforms contain no harmonics at all, only the
fundamental
,
which is
what we refer to when we talk about the pitch of a note. Consequently, a sine wave
has a very pure timbre.
The 3 main oscillators in the Virus PowerCore are capable of generating all these,
including 63 additional
spectral waves
of all sorts of shapes and timbres.
indigo powercore manual.book Page 27 Thursday, April 22, 2004 12:23 PM