Synthesis Engine
Synthesis Engine
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Oscillators
The branches A and B both contain an Oscillator – a source for a sine-wave signal.
The perceived sound of a sine wave is rather simple, as there is just the fundamental,
which is detected by the ear as a pitch. It lacks any further harmonics or partials in gen-
eral, so the perceived sound is devoid of any timbre.
By phase modulation, wave shaping or ring modulation, new partial tones can be
created. The resulting waveforms and spectra can vary enormously and evolve over time.
This is the foundation of a sound that later can be further manipulated by the two filters.
When a key is pressed, each oscillator synchronizes to a particular start phase. This
allows both oscillators to run in or out of phase up to the point, where they will cancel
each other out. Besides, when using unison, the individual tones can have an individual
phase oset as well. If the start phase of an oscillator is not zero, it will not start at the
zero-crossing of the sine wave. With short Attack times, a clicking will be noticeable, as
sharp transients can occur in that scenario.
The frequency of an oscillator (the number of oscillations per second) is represented as
a Pitch parameter, providing the familiar format of semitones and cents. The influence
of the position of a pressed key can be weighted by the Key Tracking parameter, adding
to the basic tuning of the oscillator. At 100% Key Tracking, the Oscillator pitch directly
corresponds to the keyboard. However, there are other possible influences on the pitch as
a modulation target, typically by the Bender. Envelope C can shi the pitch as well.
By taking use of the Scale group, the pitches of played notes can even be set to dierent
scalings apart from the familiar equidistant temperament of modern western music. If
using unison in addition, a cluster of voices will sound where the Spread parameter can
stretch the individual pitches apart from one another.
Even each oscillation cycle can vary in frequency, as provided by a Fluctuation parameter.
When Fluctuation is used, each cycle will have a random oset to the basic frequency.
This converts the simple sine-wave to a band-limited noise. At high amounts, the oscilla-
tor frequency can randomly vary between 5% and 195% per cycle, which leads to a very
irregular behavior and a wide-band spectrum. The Fluctuation can also be aected by
Envelope C.
In order to manipulate both harmonics and noisiness of the sine wave, phase modulation
(„PM“, oen also referred to as „FM“) can be exploited, as each Oscillator provides several
parameters dedicated to define the complex relations of intermodulations.
Attack
Level
Peak Level
Breakpoint Level
Sustain Level
Time
Note On Note O
Decay 1 Decay 2 Release
Attack
Level
Peak Level
Breakpoint Level
Breakpoint Level
Sustain Level
Sustain Level
Time
Note On Note O
Decay 1 Decay 2 Release
Envelope A & B
Envelope C
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