The Complete Handbook of Sound Synthesizers

Chapter 1: Understanding Sound Synthesizers

Understanding Sound Synthesizers

The sound synthesizer is, at its core, a tool for creating audible waveforms that do not occur in nature with any kind of convenience or reproducibility. A piano string, a drum head, and a human vocal cord all produce sound through physical vibration. A synthesizer produces sound through electrical circuits that generate and shape a signal. This distinction is fundamental. When you press a key on a piano, you are triggering a hammer to strike a string. When you press a key on a synthesizer, you are opening a gate, a control signal that tells the electronics to start producing a tone. The key itself is essentially a switch, not a mechanical actuator. This is why a synthesizer can sound like anything from a flute to a spaceship; it is not bound by the physics of an acoustic object.

To understand how a synthesizer works, you must understand the concept of a signal path. Think of it as an assembly line for sound. Raw, unprocessed electrical vibrations are created, and then they travel through a series of processing stages that alter their character. Each stage is a functional block with a specific job. While there are many different types of synthesizers, the vast majority of them follow a fundamental architecture: an oscillator, a filter, an amplifier, and a set of modulators. The specific order and design of these blocks are what give each instrument its unique voice.

The Primary Signal Path

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