Moog Music Minimoog Voyager XL - Manual (Page 16)

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Voyager XL User’s Manual - The Components
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Voyager XL User’s Manual - The Components
B. The Oscillator Section
The Oscillators are the main sound source of the Voyager XL. The oscillators are all analog Voltage Con-
trolled Oscillators, or VCOs. They feature a temperature regulation circuit that provides them with excel-
lent tuning stability. The VCOs can produce a total musical range of 8 1⁄2 octaves! In addition, the frequency
of oscillator 3 can be set to the sub-audio range (<20Hz) for use as an auxiliary LFO.
Oscillator 1 performs as a master oscillator to which Oscillator 2
and 3 are tuned. The timbres of the oscillators are adjusted by their
variable Waveform controls. In addition, there are switches for
Oscillator 2 sync to 1; linear frequency modulation of Oscillator 1
by 3; Oscillator 3 keyboard control on/off; and Oscillator 3 Lo or Hi
frequency range. The frequencies of the Oscillators are controlled
by a number of sources. The main source is the pitch CV generated
by keyboard or by MIDI Note ONs. A glide circuit can be switched
in between the Keyboard CV and the oscillators to slow the voltage
changes between notes, resulting in a glissando effect. The Keyboard
CV then is mixed with the Octave switch CV, the Frequency control
(Oscillators 2 and 3), the Pitch Bend Wheel, the Fine Tune control,
and the output of the Mod Busses when the ‘Pitch’ destination is
selected.
Oscillator Section Controls:
Octave:
Each Oscillator has a 6-position OCTAVE switch that selects the relative frequency range. To hear how it
works, turn off Oscillators 2 and 3 in the Mixer. Turn Oscillator 1 on and set its level to 5. Play a note on
the keyboard and rotate the Oscillator 1 octave switch clockwise one click – the note will rise an octave.
You can use this control to change the frequency range that the keyboard controls. The panel markings 32’
up to 1’ are octave standards based on organ stops. On the 16’ setting, MIDI Note number 93 is A440
(equivalent to the “A” key above middle C) .
Frequency:
Oscillators 2 and 3 have a FREQUENCY control. When the control is in the center position, the oscillators
should be in unison with the frequency of Oscillator 1 (when the octave switches for all three oscillators
are in the same position). The Frequency control can change the pitch of Oscillator 2 or 3 a total of +/- 7
semitones relative to Oscillator 1. This allows more than one frequency to be played when a key is pressed.
Adjusting the frequency of Oscillator 2 & 3 to be slightly out of tune with Oscillator 1 results in the classic
“oscillator beating” chorus sound.
NOTE: The Oscillator FREQUENCY controls have no calibration - sometimes unisons are
made with the controls a little left or right of center. Oscillator 1 does not have a Frequency
control because it is designed to serve as a reference oscillator for the other 2 oscillators.