Musical form

Thought-form of the Music of Gounod, according to Annie Besant and C.W. Leadbeater in Thought Forms (1901)

The term musical form (or musical architecture) refers to the overall structure or plan of a piece of music, and it describes the layout of a composition as divided into sections. In the tenth edition of The Oxford Companion to Music, Percy Scholes defines musical form as "a series of strategies designed to find a successful mean between the opposite extremes of unrelieved repetition and unrelieved alteration."

According to Richard Middleton, musical form is "the shape or structure of the work." He describes it through difference: the distance moved from a repeat; the latter being the smallest difference. Difference is quantitative and qualitative: how far, and of what type, different. In many cases, form depends on statement and restatement, unity and variety, and contrast and connection.

Levels of organisation

The founding level of musical form can be divided into two parts:

• The arrangement of the pulse into unaccented and accented beats, the cells of a measure that, when harmonized, may give rise to a motif or figure.
• The further organization of such a measure, by repetition and variation, into a true musical phrase having a definite rhythm and duration that may be implied in melody and harmony, defined, for example, by a long final note and a breathing space. This "phrase" may be regarded as the fundamental unit of musical form: it may be broken down into measures of two or three beats, but its distinctive nature will then be lost. Even at this level, the importance of the principles of repetition and contrast, weak and strong, climax and repose, can be seen. (See also: Meter (music)) Thus, form may be understood on three levels of organization. For the purpose of this exposition, these levels can be roughly designated as passage, piece, and cycle.

Passage

The smallest level of construction concerns the way musical phrases are organized into musical sentences and "paragraphs" such as the verse of a song. This may be compared to, and is often decided by, the verse form or meter of the words or the steps of a dance.

For example, the twelve bar blues is a specific verse form, while common meter is found in many hymns and ballads and, again, the Elizabethan galliard, like many dances, requires a certain rhythm, pace and length of melody to fit its repeating pattern of steps. Simpler styles of music may be more or less wholly defined at this level of form, which therefore does not differ greatly from the loose sense first mentioned and which may carry with it rhythmic, harmonic, timbral, occasional and melodic conventions.

In the analysis of musical form, any components that can be defined on the time axis (such as sections and units) are conventionally designated by letters. Upper-case letters are used for the most fundamental, while lower-case letters are used for sub-divisions. If one such section returns in a varied or modified form, a numerical digit or an appropriate number of prime symbols appears after the letter. Even at this simplest level, there are patterns that may be re-used on larger timescales. For example, consider the analogy with rhyme schemes;

The following verse is composed of two differently-rhymed couplets (AABB), and thus its organization is binary or "twofold".

Twinkle, twinkle, little star,

How I wonder what you are.

Up above the world so high,

like a diamond in the sky.

However, in the verse below, there is a rhyme repeated in the second line, then a variant in the third line, two half-lines sharing a new rhyme, followed by a final return to the first arrangement in the last line (AABA), and thus its organization is song form. Ternary form or "threefold" is (ABA).

There once was a fellow from Leeds

Who swallowed a packet of seeds.

In less than an hour he burst into flower

And he died trying to pull up the weeds.

However, as music educator Stewart Macpherson stated, there is a preference at all levels of musical organization for groupings of two, four, eight over other divisions, so that even a ternary form is often extended by repetition of the first subject into a "fourfold" structure so that composers must guard against excessive "squareness".

Pieces

The next level concerns the entire structure of any single self-contained musical piece. If the hymn, ballad, blues or dance alluded to above simply repeats the same musical material indefinitely then the piece is said to be in strophic form overall. If it repeats with distinct, sustained changes each time, for instance in setting, ornamentation or instrumentation, then the piece is a theme and variations. If two distinctly different themes are alternated indefinitely, as in a song alternating verse and chorus or in the alternating slow and fast sections of the Hungarian czardas, then this gives rise to a simple binary form. If the theme is played (perhaps twice), then a new theme is introduced, the piece then closing with a return to the first theme, we have a simple ternary form.

Great arguments and misunderstanding can be generated by such terms as 'ternary' and 'binary', as a complex piece may have elements of both at different organizational levels. A minuet, like any Baroque dance, generally had simple binary structure (AABB), however, this was frequently extended by the introduction of another minuet arranged for solo instruments (called the trio), after which the first was repeated again and the piece ended—this is a ternary form—ABA: the piece is binary on the lower compositional level but ternary on the higher. Organisational levels are not clearly and universally defined in western musicology, while words like "section" and "passage" are used at different levels by different scholars whose definitions, as Schlanker points out, cannot keep pace with the myriad innovations and variations devised by musicians.

Cycle

The grandest level of organization may be referred to as "cyclical form". It concerns the arrangement of several self-contained pieces into a large-scale composition. For example, a set of songs with a related theme may be presented as a song-cycle, whereas a set of Baroque dances were presented as a suite. The opera and ballet may organize song and dance into even larger forms. This level of musical form, though it again applies and gives rise to different genres, takes more account of the methods of musical organisation used. For example: a symphony, a concerto and a sonata differ in scale and aim, yet generally resemble one another in the manner of their organization. The individual pieces which make up the larger form may be called movements.

Single forms

Scholes suggested that European classical music had only six stand-alone forms: simple binary, simple ternary, compound binary, rondo, air with variations, and fugue (although musicologist Alfred Mann emphasized that the fugue is primarily a method of composition that has sometimes taken on certain structural conventions.)

Where a piece cannot readily be broken down into sectional units (though it might borrow some form from a poem, story or programme), it is said to be through-composed. Such is often the case with a fantasia, prelude, rhapsody, etude (or study), symphonic poem, Bagatelle, impromptu, etc. Charles Keil classified forms and formal detail as "sectional, developmental, or variational."

Sectional form

This form is built from a sequence of clear-cut units that may be referred to by letters but also often have generic names such as introduction and coda, exposition, development and recapitulation, verse, chorus or refrain, and bridge. Introductions and codas, when they are no more than that, are frequently excluded from formal analysis. All such units may typically be eight measures long. Sectional forms include:

Strophic form

Main article: Strophic form

This form is defined by its "unrelieved repetition" (AAAA...).

Medley or "chain" form

Medley, potpourri or chain form is the extreme opposite, that of "unrelieved variation": it is simply an indefinite sequence of self-contained sections (ABCD...), sometimes with repeats (AABBCCDD...). Examples include orchestral overtures, which are sometimes no more than a string of the best tunes of the show to come.

Binary form

Main article: Binary form

Binary form in major and minor keys. Each section must be at least three phrases long.

This form uses two sections (AB...), each often repeated (AABB...). In 18th-century western classical music, "simple binary" form was often used for dances and carried with it the convention that the two sections should be in different musical keys but same rhythm, duration and tone. The alternation of two tunes gives enough variety to permit a dance to be extended for as long as desired.

Ternary form

Main article: Ternary form

This form has three parts. In Western classical music a simple ternary form has a third section that is a recapitulation of the first (ABA). Often, the first section is repeated (AABA). This approach was called da capo (i.e. "repeat from the top") form. Later, it gave rise to the 32-bar song, with the B section then often referred to as the "middle eight". A song has more need than a dance of a self-contained form with a beginning and an end of course.

Rondo form

Main article: Rondo form

This form has a recurring theme alternating with different (usually contrasting) sections called "episodes". It may be asymmetrical (ABACADAEA) or symmetrical (ABACABA). A recurring section, especially the main theme, is sometimes more thoroughly varied, or else one episode may be a "development" of it. A similar arrangement is the ritornello form of the Baroque concerto grosso. Arch form (ABCBA) resembles a symmetrical rondo without intermediate repetitions of the main theme. It is normally used in a round.

Variational form

Main article: Variation (music)

Variational forms are those in which variation is an important formative element.

Theme and Variations: a theme, which in itself can be of any shorter form (binary, ternary, etc.), forms the only "section" and is repeated indefinitely (as in strophic form) but is varied each time (A,B,A,F,Z,A), so as to make a sort of sectional chain form. An important variant of this, much used in 17th-century British music and in the Passacaglia and Chaconne, was that of the ground bass—a repeating bass theme or basso ostinato over and around which the rest of the structure unfolds, often, but not always, spinning polyphonic or contrapuntal threads, or improvising divisions and descants. This is said by Scholes (1977) to be the form par excellence of unaccompanied or accompanied solo instrumental music. The Rondo is often found with sections varied (AA¹BA²CA³BA⁴) or (ABA¹CA²B¹A).

Developmental form

Main article: Musical development

Developmental forms are built directly from smaller units, such as motifs, combined and worked out in different ways, perhaps having a symmetrical or arch-like underpinning and a progressive development from beginning to end. By far the most important in Western classical music is:

Sonata-allegro form

Main article: Sonata form

This form, also known as sonata form, first movement form, compound binary, ternary and a variety of other names, developed from the binary-formed dance movement described above but is almost always cast in a greater ternary form having the nominal subdivisions of Exposition, Development and Recapitulation. Usually, but not always, the "A" parts (Exposition and Recapitulation, respectively) may be subdivided into two or three themes or theme groups which are taken asunder and recombined to form the "B" part (the development)—thus e. g. (AabB[dev. of a and/or b]A¹ab¹+coda). This developmental form is generally confined to certain sections of the piece, as to the middle section of the first movement of a sonata, though 19th-century composers such as Berlioz, Liszt and Wagner made valiant efforts to derive large-scale works purely or mainly from the motif.

Chester (1970) distinguished this as "extensional music", that "produced by starting with small components—rhythmic or melodic motifs, perhaps—and then 'developing' these through techniques of modification and combination." "Intensional music", meanwhile, "starts with a framework—a chord sequence, a melodic outline, a rhythmic pattern—and then extends itself by repeating the framework with perpetually varied inflections to the details filling it in."

Cyclical forms

Opera was originally modelled upon classical drama and takes much of its form from its libretto and narrative. For many years, ballet was a component of opera, not in itself narrative, but having the form of a suite of set dances included at some appropriate moment in the story such as a festival or wedding. It emerged as a separate form, supplying its own narrative or representation, during the 19th century. At the same time, the song cycle emerged, which is a set of related songs (as the suite is a set of related dances). The oratorio took shape as a narrative, often religious, recounted—rather than acted—by the singers.

The sonata, symphony, and concerto were all developed by major composers of the Viennese school (Haydn, Mozart and Beethoven primarily) along the same formal lines into distinctively musical forms limited little by the forms of song, dance or ceremony. Other forms of music, such as the Catholic mass and requiem, are largely shaped by, and subordinated to, their texts and ceremonial functions.

See also

• Developing variation
• List of musical forms by era
• Song structure

External links

• Lessons in Music Form by Percy Goetschius, 1904
• Study Guide for Musical Form: A Complete Outline of Standardized Formal Categories and Concepts by Robert T. Kelley
• A Practical Guide to Musical Composition by Alan Belkin
• Morphopoiesis: A General Procedure for Structuring Form by Panayiotis Kokoras
• Klorman, Edward. 2014. "Musical Form: Mapping the Territories" in Music Theory Online 20.2.