Operation Manual

SUBTRACTOR SYNTHESIZER
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✪ Experiment with different oscillator parameters such as phase offset
modulation, changing the waveforms etc. and listen to how they affect
the sound of frequency modulation.
Using the Noise Generator as the Modulator source
As explained earlier, the Noise Generator is internally routed to the Osc 2 output.
Hence, if you deactivate Osc 2, and activate the Noise Generator while using FM, the
noise will be used to frequency modulate Osc 1.
✪ With the Noise Generators default settings, this will sound much like col-
ored noise. But by changing (lowering) the Noise Generator Decay pa-
rameter, so that the noise modulates only the attack portion of the sound
can produce more interesting results. You could also use a combination
of noise and Osc 2.
Ring Modulation
Ring Modulators basically multiply two audio signals together. The ring modulated
output contains added frequencies generated by the sum of, and the difference be-
tween, the frequencies of the two signals. In the Subtractor Ring Modulator, Osc 1 is
multiplied with Osc 2 to produce sum and difference frequencies. Ring modulation
can be used to create complex and enharmonic, bell-like sounds.
1. Select an Init Patch by selecting “Initialize Patch” from the Edit menu.
Save any current settings you wish to keep before initializing.
2. Activate Ring Modulation with the button in the lower right corner of the os-
cillator section.
3. Activate Osc 2.
You need to activate Osc 2 before any ring modulation can happen.
4. Turn the Osc Mix knob fully to the right, so that only the sound of Osc 2 is
heard.
Osc 2 provides the ring modulated output.
5. If you play a few notes while varying the frequency of either oscillator, by us-
ing the Semitone spin controls, you can hear that the timbre changes dra-
matically.
If the oscillators are tuned to the same frequency, and no modulation is applied to
either the Osc 1 or 2 frequency, the Ring Modulator won’t do much. It is when the
frequencies of Osc 1 and Osc 2 differ, that you get the “true” sound of ring mod-
ulation.
The Filter Section
In subtractive synthesis, a filter is the most important tool for shaping the overall tim-
bre of the sound. The filter section in Subtractor contains two filters, the first being a
multimode filter with five filter types, and the second being a low-pass filter. The com-
bination of a multimode filter and a lowpass filter can be used to create very complex
filter effects.
Filter 1 Type
With this multi-selector you can set Filter 1 to operate as one of five different types of
filter. The five types are illustrated and explained on the following pages:
D 24 dB Lowpass (LP 24)
Lowpass filters lets low frequencies pass and cuts out the high frequencies. This
filter type has a fairly steep roll-off curve (24dB/Octave). Many classic synthesizers
(Minimoog/Prophet 5 etc.) use this filter type.
The darker curve illustrates the roll-off curve of the 24dB Lowpass Filter. The lighter curve in the
middle represents the filter characteristic when the Resonance parameter is raised.