Oberheim OB 12, Руководство по эксплуатации

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OB 12
Z-Domain Synthesizer
7.2 SETTING the SECOND WAVEFORM (OSC.2)
148
•
[LFO1 DEPTH]: regulates the depth of the frequency modulation by LFO1 (first low frequency
oscillator) on the pitch (with cyclic variation) of the Osc.1 signal, thus generating vibrato effects.
With the knob turned completely to the right, Osc.1 will be affected by the maximum depth of
LFO1 modulation. With the knob in central position, the oscillator will be unaffected by the
modulation, and when it is turned completely to the left, the modulation depth will be at the
maximum but with opposite phase to that obtained with the knob turned to the right.
•
[PWM DEPTH]
(Pulse With Modulation Depth)
: this trimmer can be used to regulate the depth of
modulation of only the square waveform generated by Osc.1 (and thus not the outcome of
the three basic waveforms) by the source specified by means of the button below the trimmer
itself. This button allows selection of the following as source of the modulating signal:
- LFO1: the first low frequency oscillator
-
LFO2: the second low frequency oscillator
- EG: the envelope generator
The selection will be confirmed by illumination of the corresponding LED.
N.B.: If you have deleted the square waveform (by means of the [WAVE MIX] slider or the
[WAVE SELECT] button referred to this signal) you will not be able to hear any acoustic effect
generated by this control.
As for Oscillator 1, Oscillator 2 also generates the basic waveform of the sound you are creating.
Therefore, the two waveforms can be mixed using the BALANCE sliders in the OSC.COMMON
section to obtain the most widely varying sound combinations.
Since the functions of these two sections are virtually identical, the panel section is also very
much the same. As we can see, the controls relating to the second oscillator are:
•
[WAVE MIX]: you can use
these three sliders to mix
the three waveforms which
will then form the output of
the second oscillator. As
described on the panel, the
first slider controls the level
of the sawtooth waveform,
the second controls the
triangular waveform and the
third the square waveform.