User Guide

7
In general, “synthesis” refers to the generation of sound through a group of amplified circuits
over which the programmer/performer has power to change volume, pitch, timbre and
articulation. The Minimoog Voyager is based on what is called “subtractive synthesis”. This method
of synthesis employs a harmonically rich (think bright-sounding) source material, and then removes
frequency components to create the desired sound. The basic components of subtractive
synthesis and their definitions follow:
Oscillator: A circuit that electronically “vibrates”. When used as a sound source, an oscillator is
the electronic equivalent of a vibrating reed, or string. When amplified, an oscillator produces a
pitched sound whose frequency is determined by one or more control voltages (see below for
more info). Changes to these voltages correspond to changes in pitch. An oscillator’s vibration
can have different shapes or waveforms, which are described below. The Voyager has three
oscillators.
Waveform: The shape of an oscillator’s vibration. This determines its timbre. Commonly used
waveforms in subtractive synthesis are sawtooth, triangle, square, or rectangular. Different
waveforms have different timbres. A sawtooth has the greatest number of harmonics, and sounds
bright and buzzy. A square wave has only odd harmonics, and sounds bright, but hollow, like a
clarinet. A rectangular wave can vary in shape, but typically has a bright but thin sound, and a
triangle wave’s harmonics are so low in amplitude that it sounds muted and flutelike (figure 6).
Mixer: A circuit for combining multiple sound sources or signals. The Voyager’s Mixer allows you to
select and set the level for up to 5 different sound sources.
Filter: A circuit that removes some frequencies and allows other frequencies to pass through the
circuit. A filter has a cutoff frequency that determines the point at which frequencies begin to be
removed. There are different types of filters that perform different functions.