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• Stereo Width knob: Distributes the output signals of the filter bands in the stereo field.
• At the left position, the outputs of all bands are centered.
• At the centered position, the outputs of all bands ascend from left to right.
• At the right position, the bands are output—alternately—to the left and right
channels.
EVOC 20 TrackOscillator
The EVOC 20 TrackOscillator is a vocoder with a monophonic pitch tracking oscillator.
The tracking oscillator tracks, or follows, the pitch of a monophonic input signal. If the
input signal is a sung vocal melody, the individual note pitches are tracked and mirrored,
or played, by the synthesis engine.
The EVOC 20 TrackOscillator features two formant filter banks, an analysis bank, and a
synthesis filter bank. Each offers multiple input options.
You can capture an analysis signal source by using the audio arriving at the input of the
channel strip that the EVOC 20 TrackOscillator is inserted in, or by using a side chained
signal from another channel strip.
The synthesis source can be derived from the audio input of the channel strip that the
EVOC 20 TrackOscillator is inserted in, a side chain signal, or the tracking oscillator.
As you can freely select both the analysis and synthesis input signals, the EVOC 20
TrackOscillator is not limited to pitch tracking effects. It is extremely useful for unusual
filter effects. For example, you could filter an orchestral recording on one channel strip
with train noises side chained from another channel strip. Another great use is for
processing drum loops with side chained signals, such as other drum loops or rhythmic
guitar, clavinet and piano parts.
What Is a Vocoder?
The word vocoder is an abbreviation for VOice enCODER. A vocoder analyzes the sonic
character of the audio signal arriving at its analysis input and transfers it to the synthesizer’s
sound generators. The result of this process is heard at the output of the vocoder.
The classic vocoder sound uses speech as the analysis signal and a synthesizer sound as
the synthesis signal. This sound was popularized in the late 1970s and early 1980s. You’ll
probably know it from tracks such as “O Superman” by Laurie Anderson, “Funky Town”
by Lipps Inc., and numerous Kraftwerk pieces—such as “Autobahn,” “Europe Endless,”
“The Robots,” and “Computer World.”
In addition to these “singing robot” sounds, vocoding has also been used in many
films—such as with the Cylons in Battlestar Galactica, and most famously, with the voice
of Darth Vader from the Star Wars saga.
107Chapter 6 Filter Effects