8 THE BASICS OF SUBTRACTIVE SYNTHESIS

Subtractive synthesis appeared at the end of the 1960’s, giving birth to the first analog synthesizers: Moog, ARP, EMS, Oberheim, Roland (SH, Juno or Jupiter series), Yamaha (CS series) and Korg (MS and PS series).

Of all forms of audio synthesis, subtractive is one of the oldest, and to this day, the most frequently employed by sound designers and musicians alike. This is due to the simplicity with which complex sounds can be created, over the more difficult types of synthesis, many of which employ elements of subtractive synthesis as well, such as low-pass filtering. As a basic overview to subtractive synthesis, one may consider any sound created, either in real life or on the synthesizer of your choice, as consisting of a number of sine waves, or harmonics grouped together. In subtractive synthesis, we start with a harmonically rich sound such as a saw wave, and through filtering, we remove the sine waves (or harmonics) that we do not want. This as you can imagine is much more complex than turning a filter control knob!

The Jupiter-8V you own shows some very good examples of the subtractive synthesis possibilities.

8.1THE MAIN ELEMENTS

8.1.1 The Oscillator or VCO

The oscillator or VCO (Voltage Controlled Oscillator) is the starting module (with the noise module which is often classed among the oscillators) for the creation of a sound on an analog system.

It will generate the initial sound signal. We can think of the oscillator like a violin string that once stroked or plucked, vibrates to create its sound.

Oscillator Section on the Jupiter 8

The main oscillator settings are:

The pitch determined by the oscillation frequency. You can set the frequency of the oscillator with 3 controllers:

The “RANGE” parameter allows setting the tuning of the oscillator by octave. Usually, on four octaves 16', 8', 4', 2'. (The unities are indicated in feet, referring to the sizes of the pipes of church organs). The Jupiter-8 also has a “LOW” range to set the oscillator2 to low frequencies.

ARTURIA – JUPITER-8V – USER’S MANUAL

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Arturia 2 manual Main Elements, Oscillator or VCO