Home > Baker's Student Encyclopedia of Music > Harmony

A combination of TONES or CHORDS, CONSONANT or DISSONANT. Also, the CONTRAPUNTAL texture of a HOMOPHONIC piece, as two- or three-part harmony.

The Greek word HARMONÍA referred to an ideal music, with an artful coordination between high and low sounds and a balanced rhythmic and melodic arrangement of slow and fast musical phrases. However, for at least the last 1,000 years, the word harmony has meant the simultaneous sounding of several melodies, represented in musical notation by vertical position, while melody was linear, notated horizontally. Counterpoint contains both harmonic and melodic elements because it is a harmonious synchronization of linear melodies.

When harmony first emerged as a definite technique, it was entirely consonant, limited to the use of perfect concords, the OCTAVE and the FIFTH. Because a perfect fifth subtracted from an octave formed a perfect fourth, consonant intervals incorporated perfect octaves, fifths, and fourths. The decisive step toward traditional harmony occurred in the late Middle Ages, when thirds and sixths were adopted as acceptable consonant intervals. Originally, the major TRIAD was only implied by the statement of the TONIC and fifth. Curiously, this continued to be the rule until the 16th century, when final triads finally acquired the essential third step of the scale.

With the birth of FAUXBOURDON, FIRST INVERSION of the major chord was introduced. Dissonant passing tones became more and more frequent. FIGURED BASS appeared as harmonic shorthand that opened the way toward the use of triads and seventh chords on all degrees of the scale.

In the 17th century, harmonic composition began to separate itself from COUNTERPOINT. In the next century counterpoint developed into a sublime art in the music of JOHANN SEBASTIAN BACH, but elsewhere harmony gradually became a vertical group of tones with limited independence of its component parts. However, Bach's sons embraced harmonic composition governed by the laws of chord progressions. The melody was emphasized, and the bass became the source of the harmony part.

Four-part harmony emerged at the end of the BAROQUE era, around 1750. The tonic (1st), subdominant (4th), and dominant (5th) triads are the main determinants of tonality, because these three triads contain all seven notes of the diatonic scale. In major keys, these triads are major, and in minor the tonic and subdominant are minor, but the dominant is made major by raising the seventh degree (creating the LEADING TONE), which is the middle tone of the major dominant triad.

Four-part harmony makes it possible to achieve complete sets of seventh chords on all degrees of the scale, as well as the diminished-seventh chord that occurs functionally upon the leading tone in a harmonic minor key. In strict harmony, triads having a diminished or augmented fifth are not allowed. Consequently, a triad built on the seventh degree of either the major or harmonic minor mode cannot be used, nor the SUPERTONIC triad (based on the 2nd scale degree) in minor keys. However, this rule was less strictly enforced in time.

Consecutive intervals, that is, a perfect fifth or octave moving in the same direction to another perfect fifth or octave, particularly between outer voices, are forbidden. Parallel movement of different intervals toward fifths or octaves, known as hidden intervals, is also taboo. A fifth or an octave can be reached only by contrary motion. Any number of examples from Bach's chorales or other well-known sources can be used to discredit this stern code.

In school exercises, the four component parts are named after the voices in a vocal quartet: soprano, alto, tenor, and bass. The most important consideration in four-part harmony is voice-leading. Generally speaking, crossing of voices is not admitted—the soprano must always be the upper voice, the bass must always be the lowest, and the alto may not cross under the tenor. CONTRARY MOTION is recommended, especially between the soprano and bass. Stepwise motion is preferred. Thirds and sixths are favored because they can be used in consecutive motion.

When one voice leaps several scale degrees, the rest of the voices must move stepwise to provide counterbalance and establish proper balance. If the soprano has a melodic leap upward, then the bass ought to move stepwise, preferably in the opposite direction. If in the same direction, the bass must avoid landing on a perfect fifth or octave, which would result in hidden fifths or octaves.

By and large, an ideal exercise in four-part harmony would present an alternation of thirds and sixths between the outer voices, with occasional legitimate parallelisms. The octave is expected in almost every final cadence. The middle voices are less mobile and have less opportunity to move by leaps. Often they are stationary, maintaining the common tone between two successive chords. Each chord can be arranged in six different ways without changing the bass.

The distance between soprano and alto or between alto and tenor must not exceed an octave, but the distance between bass and tenor may be as extensive as a twelfth. When the three upper voices are bunched together within an octave, it is called CLOSE HARMONY. When these upper voices are dispersed for a total range of more than an octave, the setting is said to be in OPEN HARMONY.

A veritable harmonic revolution occurred with extraordinary suddenness toward the end of the 19th century. In the works of CLAUDE DEBUSSY and his followers the traditional rules of harmony were revised. Naked fifths and octaves moved in parallel lines as they did a thousand years before in Organum. Consecutive triads in close harmony became common, disregarding the fact that such progressions necessarily involve consecutive fifths. Parallel formations of major triads were rampant, as were consecutive chords in major keys (as in, for example, the ending of MAURICE RAVEL'S String Quartet).

Up to about 1900 every dissonant combination had to be resolved into a consonance. The 20th century brought about an emancipation of dissonances. Seconds and sevenths acquired musical citizenship and were no longer treated as outcasts. The WHOLE-TONE SCALE erased the distinction between major and minor and established a neutral mode. POLYTONALITY licensed the use of two or more tonal triads simultaneously.

Diatonic harmony has been enriched by PANDIATONICISM, which removes prohibitions of unresolved dissonances within a given tonality. It also encourages the use or two or more triads at the same time. Particularly effective are the simultaneous playing of the dominant triadic formations in close harmony in the middle register with the tonic or subdominant triads in open harmony in the bass register. Pandiatonicism found its most fruitful application in NEOCLASSICAL music, in which the component notes can be used in quartal (four-voiced) harmony. In fact, quartal harmony itself has all but succeeded the tertian (three-voiced) harmony of classical music. Quartads such as E-A-D-G , placed upon the pedal tones F-C , is a typical example.

Finally, ATONALITY and its organized development, 12-tone composition or DODECAPHONY, abolished the concept of triadic tonality altogether. It is replaced with a new concept of integrated melody and harmony wherein harmony becomes a function of the fundamental TONE-ROW.

Subdivisions of the tempered scale in quarter-tone music and even smaller microtones prosper modestly as a monophonic art, but experiments have been made in microtonal harmonies as well. Electronic music has freed harmony of all technical impediments and allows the use of precisely calculated, nontempered intervals as well as microtones.

Further harmonic terminology: Chromatic harmony has chromatic tones and modulations; compound harmony has 2 or more essential chord-tones doubled; dispersed or extended harmony, OPEN HARMONY; dissonant harmony, see DISSONANCE; essential harmony, fundamental triads of a key, or the harmonic frame of a composition minus all figuration and ornaments; false harmony, the inharmonic relation, or DISCORD produced by imperfect preparation or resolution, or by wrong notes or chords; figured harmony varies simple chords by figuration of all kinds; pure harmony, music performed in pure or just intonation; spread harmony, open harmony; strict harmony, composition according to strict rules for the preparation and resolution of dissonances; tempered harmony, music performed in tempered intonation.