Plug-in Reference

49
The included VST Instruments
OSC 3 parameters
Oscillator 3 has the following parameters:
About frequency modulation
Frequency modulation or FM means that the frequency of
one oscillator (called the carrier) is modulated by the fre-
quency of another oscillator (called the modulator).
• In Prologue, Osc 1 is the modulator, and Osc 2 and 3
are carriers.
Osc 2 could be said to be both carrier and modulator as if Freq Mod is
applied to Osc 2 it is modulated by Osc 3. If Osc 2 also uses frequency
modulation, Osc 3 will be modulated by both Osc 1 and Osc 2.
• The “pure” sound of frequency modulation is output
through the modulator oscillator(s).
This means that you should turn off the Osc 1 output when using fre-
quency modulation.
• The Freq Mod button switches frequency modulation on
or off.
Wave Mod +/- 50 This parameter dial is only active if the
Wave Mod button is activated beside the
waveform selection box. Wave modula-
tion works by adding a phase-shifted
copy of the oscillator output to itself,
which produces waveform variations. For
example if a sawtooth waveform is used,
activating WM will produce a pulse
waveform. By modulating the WM pa-
rameter with for example a LFO, classic
PWM (pulse width modulation) is pro-
duced. Wave modulation can, however,
be applied to any waveform.
Ratio 1–16 This parameter dial (which is only active
if the Freq Mod button is activated) ad-
justs the amount of frequency modula-
tion applied to oscillator 2. See “About
frequency modulation” on page 49. Is
normally referred to as FM index.
Sync button On/Off When Sync is activated, Osc 2 is slaved
to Osc 1. This means that every time Osc
1 completes its cycle, Osc 2 is forced to
reset (start its cycle from the beginning).
This produces a characteristic sound,
suitable for lead playing. Osc 1 deter-
mines the pitch, and varying the pitch of
Osc 2 produces changes in timbre. For
classic sync sounds, try modulating the
pitch of Osc 2 with an envelope or a LFO.
The Osc 2 pitch should also be set
higher than the pitch of Osc 1.
Tracking
button
On/Off When Tracking is activated, the oscillator
pitch will track the notes played on the
keyboard. If Tracking is deactivated the
oscillator pitch remains constant, regard-
less of what note is played.
Freq Mod
button
On/Off This switches frequency modulation on
or off.
Wave Mod
button
On/Off This switches wave modulation on or off.
Waveform
selector
pop-up
See “Selecting
Waveforms” on
page 47.
Sets the basic waveform for the oscillator.
Parameter Value Description
Osc 3 0–100 This controls the output level of the oscil-
lator.
Coarse +/- 48
semitones
This determines the coarse pitch for Osc
3. If FM is enabled, this determines the
frequency ratio of the oscillator regarding
Osc 1/2.
Parameter Value Description
Fine +/- 50 cent Fine tunes the oscillator pitch in cent in-
crements (100th of a semitone). If FM is
enabled, this determines the frequency
ratio of the oscillator regarding Osc 1/2.
Ratio 1–16 This parameter dial (which is only active if
the Freq Mod button is activated) adjusts
the amount of frequency modulation ap-
plied to oscillator 3. See “About frequency
modulation” on page 49. Is normally re-
ferred to as FM index.
Sync button On/Off When Sync is activated, Osc 3 is slaved
to Osc 1. This means that every time Osc
1 completes its cycle, Osc 3 is forced to
reset (start its cycle from the beginning).
This produces a characteristic sound,
suitable for lead playing. Osc 1 deter-
mines the pitch, and varying the pitch of
Osc 3 produces changes in timbre. For
classic sync sounds, try modulating the
pitch of Osc 3 with an envelope or a
LFO. The Osc 3 pitch should also be set
higher than the pitch of Osc 1.
Tracking
button
On/Off When Tracking is activated, the oscillator
pitch will track the notes played on the
keyboard. If Tracking is deactivated the
oscillator pitch remains constant, regard-
less of what note is played.
Freq Mod
button
On/Off This switches frequency modulation on
or off.
Wave Mod
button
On/Off This switches wave modulation on or off.
Waveform
selector
pop-up
See “Selecting
Waveforms” on
page 47.
Sets the basic waveform for the oscillator.
Parameter Value Description