Music Theory Vocabulary: Introduction

Sound

The sensation perceived by the organs of hearing when vibrations (sound waves) reach the ear.

Vibration (Sound Wave)

The periodic motion of a substance. Produced by one complete cycle of compression and rarefaction.

Compression

Increased air pressure

Rarefaction

Decreased air pressure

Frequency

The number of compression-rarefaction cycles that occur per unit of time (usually 1 second).

Pitch

The lowness or highness of a sound. Variations in frequency are perceived as variations in pitch.

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Greater frequency = higher pitch; lower frequency = lower pitch.

Tone

A musical sound of definite pitch.

Intensity (Amplitude)

Heard as the loudness or softness of a pitch.

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In acoustics (the science of sound) intensity is the amount of energy affecting a vibrating body. Intensity is measured in decibels.

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Gradations of intensity are indicated by dynamics.

Decibel

Unit of measurement for intensity/amplitude on a scale from 0-130.

Duration

The length of time a pitch, or tone, is sounded.

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Meter and rhythm are terms used to describe patterns of duration.

Meter

Regularly recurring pulses of equal duration, generally grouped into patterns of two, three, four, or more with one of the pulses in each group accented.

Beats

Patterns of strong and weak pulses within a meter.

Duple Meter

A basic two-beat meter. All other meters are a combination of duple and triple meters.

Triple Meter

A basic three-beat meter. All other meters are a combination of duple and triple meters.

Rhythm

A pattern of uneven durations.

While the steady beats of the meter combine to form measures, a rhythm may be a pattern of almost any length.

Timbre

The tone quality or color of a sound.

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This sound quality is determined by the shape of the vibrating body, its material (metal, wood, human tissue), and the method used to put it in motion (striking, bowing, blowing, plucking). It is also the result of the human ear’s perception of a series of tones called the harmonic series, which is produced by all instruments.

Harmonic Series

A harmonic series includes the various pitches produced simultaneously by a vibrating body.

This physical phenomenon results because the body vibrates in sections as well as in a single unit. A string, for example, vibrates along its entire length as well as in halves, thirds, quarters, and so on.

Harmonics (Partials)

The pitches produced simultaneously by the vibrating sections of the vibrating body.

The Fundamental

The first partial. Constitutes a musical tone alongside a series of partials.

The lowest frequency, perceived as the loudest. The ear identifies the fundamental as the specific pitch of a musical tone.

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Individual partials are not distinguished separately. Instead, they are heard by the ear as a blend that characterizes timbre.

Music

An art of sound and time