Harmonic tones should be familiar to you by now. They are the chord tones: root, third, or fifth. Nonharmonic tones (nonchord tones) are pitches that sound along with a chord but are not chord pitches. Most nonharmonic tones are dissonant and create intervals of a second, fourth, or seventh. Diminished or augmented intervals are also considered dissonant. The dissonance created by nonharmonic tones is calculated against the lowest-sounding tone of a chord, no matter how many other voices are present. An exception occurs when the nonharmonic tone is positioned in the lowest-sounding voice itself (usually bass). Non-harmonic tones generally occur in a pattern of three pitches:
Preceding tone (chord tone)
Nonharmonic tone (not a chord tone)
Following tone (chord tone)
A few nonharmonic tones involve patterns of more than three pitches and will be discussed later in the chapter. The various nonharmonic tones are named by the intervals between the preceding tone, the nonharmonic tone, and the following tone. Figure shows the common three-tone patterns. The nonharmonic tone is circled in each case.
Rhythmic Placement
The most important distinction among the various nonharmonic tones is whether the dissonance occurs on the beat (accented) or off the beat (unaccented). Dissonances placed on the beat are much stronger and often create a powerful emotional impact, whereas those placed off the beat generally pass almost unnoticed smoothing out melodic lines. Some nonharmonic tones occur in both accented and unaccented contexts; others appear only as accented or as unaccented dissonances.
Unaccented Nonharmonic Tones
The common unaccented nonharmonic tones are the unaccented passing tone, unaccented neighboring tone, escape tone, and anticipation.
Unaccented Passing Tone
Unaccented Neighboring Tones
Escape Tones
Escape tones occur only as unaccented nonharmonic tones. Figure shows the most common pattern, in which a step upward is followed by a skip downward by a third.
Anticipation
Anticipations occur only as unaccented nonharmonic tones. Figure shows two common patterns.
Accented Nonharmonic Tones
The common accented nonharmonic tones are the accented passing tone, accented neighboring tone, suspension, retardation, and appoggiatura.
Accented Passing Tone
Accented Neighboring Tone
Suspension
The suspension occurs only as an accented nonharmonic tone. The melodic pattern of the suspension figure is always as follows: the preparation, the suspension, and the resolution.
The suspended tone (the middle tone of the figure) is always dissonant. Suspensions are designated by the interval forming the suspended tone and resolution with the lowest sounding voice.
Remember that suspensions occur only between two voices—even in four-voice writing. You may ignore the other voices when considering the preparation, suspension, and resolution. The following are suspensions found in a four-voice setting.
Suspensions can occur simultaneously in pairs, have decorated resolutions, occur in chains
, or be accompanied by a changing bass line.
Retardation
A retardation is a nonharmonic tone similar to a suspension, except that the resolution is upward instead of downward.
Appoggiatura
The appoggiatura is a nonharmonic tone that is approached by skip and resolved by step in the opposite direction. It generally occurs as an accented nonharmonic tone.
The Haydn piano sonata excerpt that follows includes a suspension, an appoggiatura, and a retardation. Although the retardation in Figure 5.29 looks similar to a grace note, performance practice dictates that the retardation be performed on beat one—not before the beat.
Pedal Tone
A pedal tone (also called a pedal point) is a held or repeated note, usually in the lowest voice, that alternates between consonance and dissonance with the chord structures above it. Thus, the dissonances are created by the moving chords above rather than the pedal tone itself. When a pedal tone occurs above other voices, it is called an inverted pedal tone.
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