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Table Of Contents
An Overview of Subtractive Synthesizer Components
The front panel of most subtractive synthesizers contains a collection of similar signal
generating and processing modules—coupled with a number of modulation and control
modules. The signal-generating and processing modules typically run left to right,
mirroring the actual synthesizer signal flow.
Basic Synthesizer
Input
Output
Global ctrl Modulator
Amplifier
Filter
Oscillator
Signal Generating and Processing Components
Oscillators: Generate the basic signal. This is usually a waveform that is rich in harmonics
(see Oscillators). Many synthesizers offer more than one oscillator.
Filter section: Used to alter the basic signal by filtering out (removing) portions of the
frequency spectrum. Many synthesizers offer a single filter, which is applied universally
to all oscillator signals. Multioscillator synthesizers can provide multiple filters, allowing
each oscillator signal to be filtered in a different way (see Filters).
Amplifier section: Used to control the level of the signal over time. The amplifier features
a module known as an envelope, which is broken down into several elements that
provide level control for the beginning, middle, and end portions of your sound. Simple
synthesizers generally offer a single envelope, which is used to control the oscillator
(and filter) over time. More complex synthesizers can feature multiple envelopes (see
Envelopes in the Amplifier Section).
Modulation and Control Components
Modulators: Used to modulate the signal-generating and processing components.
Modulations can be machine-based—automatically generated by a synthesizer
component—or can be manually activated by using the modulation wheel, for example.
Most synthesizers provide a component called an LFO (low frequency oscillator) to
provide a waveform that modulates the signal. See Modulation.
354 Appendix Synthesizer Basics