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 organization
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.
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, timbre, occasional and melodic conventions.
Notation
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.
Contrast with the following verse, were the rhyme is repeated in the second line, followed by a variant in the third line – two half-lines sharing a new rhyme – and a 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.
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. Organizational 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 Shankar 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 organization 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.
See also
LETTERING (Practical)
LETTERING
SINGING IN PARTS AND CADENCE IDENTIFICATION
KNITTING
CHOREOGRAPHY