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3.4: Musical Form

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    72363
  • Photo of Harvard band forming music notes on field, Harvard vs. Brown, 1949
    Harvard band forming music notes on field, Harvard vs. Brown, 1949

    Form Is the Basic Structure

    Every piece of music has an overall plan or structure, the “big picture,” so to speak. This is called the form of the music.

    Musical forms offer a great range of complexity. Most listeners will quickly grasp the form of a short and simple piece, or of one built from many short repetitions. It is also easier to recognize familiar musical forms. The average American, for example, can distinguish easily between the verses and refrain of any pop song, but will have trouble recognizing what is going on in a piece of music for Balinese gamelan. Classical music traditions around the world tend to encourage longer, more complex forms which may be difficult to recognize without the familiarity that comes from study or repeated hearings.

    You can enjoy music without recognizing its form, of course. But understanding the form of a piece helps a musician put together a more credible performance of it. Anyone interested in music theory or history, or in arranging or composing music, must have a firm understanding of form. And being able to “see the big picture” does help the listener enjoy the music even more.

    Describing Form

    Musicians traditionally have two ways to describe the form of a piece of music. One way involves labeling each large section with a letter. The other way is to simply give a name to a form that is very common.

    Labeling Form with Letters

    Letters can be used to label the form of any piece of music, from the simplest to the most complex. Each major section of the music is labeled with a letter; for example, the first section is the A section. If the second section (or third or fourth) is exactly the same as the first, it is also labeled A. If it is very much like the A section, but with some important differences, it can be labeled A’ (pronounced “A prime”). The A’ section can also show up later in the piece, or yet another variation of A, A” (pronounced “A double prime”) can show up, and so on.

    The first major section of the piece that is very different from A is labeled B, and other sections that are like it can be labeled B, B’, B”, and so on. Sections that are not like A or B are labeled C, and so on.

    How do you recognize the sections? With familiar kinds of music, this is pretty easy. With unfamiliar types of music, it can be more of a challenge. Whether the music is classical, modern, jazz, or pop, listen for repeated sections of music. Also, listen for big changes, in the rhythm, melody, harmony, texture, and timbre. A new section that is not a repetition will usually have noticeable differences in more than one of these areas.

    Most folk and popular music features simple forms that encourage participation.

    Practice identifying some easy musical forms. Pick some favorite songs and listen to each repeatedly until you are satisfied that you have identified its full form using letters and primes. Compare the forms of the tunes to spot similarities and differences.

    Listen for:

    • Verses have the same melody but different words.
    • Refrains have the same melody and the same words.
    • Bridge Sections are new material that appears late in the song, usually appearing only once or twice, often in place of a verse and usually leading into the refrain.
    • Instrumentals are important sections that have no vocals. They can come at the beginning or end, or in between other sections. Is there more than one? Do they have the same melody as a verse or refrain? Are they similar to each other?

    While discussing a piece of music in detail, musicians may also use letters to label smaller parts of the piece within larger sections, even down to labelling individual phrases. For example, the song “The Girl I Left Behind” has many verses with no refrain, an A A’ A”-type form. However, a look at the tune of one verse shows that within that overall form is an A A’ B A” phrase structure.

    Listen: “The Girl I Left Behind”

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    Phrase Structure in “The Girl I Left Behind.” In detailed discussions of a piece of music, smaller sections, and even individual phrases, may also be labeled with letters, in order to discuss the piece in greater detail. The A A B A form of this verse is very common, found in verses of everything from folk to jazz to pop music. Verses of blues songs are more likely to have an A A’ B form.

    Naming Forms

    Often a musical form is given a name. For example, if a piece of music is called a “theme and variations” and “rondo”. (A theme and variations would follow an A A’ A” A”’… structure, with each section being a new variation on the theme in the first section. A rondo follows an A B A C A … structure, with a familiar section returning in between sections of new music.)

    Also, many genres of music tend to follow a preset form, like the “typical pop song form” in the table of familiar forms above. A symphony, for example, is associated with a particular form: three or four (depending on when it was written) main sections, called movements. They expect a moment of silence in between movements, and also expect the movements to sound very different from each other; for example if the first movement is fast and loud, they might expect that the second movement would be slow and quiet.

    But it is important to remember that forms are not sets of rules that composers are required to follow. Some symphonies don’t have silence between movements, and some don’t use the sonata form in any of their movements. Plenty of marches have been written that don’t have a trio section, and the development section of a sonata movement can take unexpected turns. And hybrid forms, like the sonata rondo, can become popular with some composers. The composer is always free to experiment with the overall architecture of the piece.

    Being able to spot that overall architecture as we listen – knowing, so to speak, which room we are in right now – gives us important clues that help us understand and appreciate the music.

    Some Common Forms

    • Through-composed – One section (usually not very long) that does not contain any large repetitions. If a short piece includes repeated phrases, it may be classified by the structure of its phrases.
    • Strophic – Composed of verses. The music is repeated sections with fairly small changes. May or may not include a refrain.
    • Variations – One section repeated many times. Most commonly, the melody remains recognizable in each section, and the underlying harmonic structure remains basically the same, but big changes in rhythm, tempo, texture, or timbre keep each section sounding fresh and interesting. Writing a set of variations is considered an excellent exercise for students interested in composing, arranging, and orchestration.
    • Jazz standard song form – Jazz utilizes many different forms, but one very common form is closely related to the strophic and variation forms. A chord progression in A A B A form (with the B section called the bridge) is repeated many times. On the first and last repetition, the melody is played or sung, and soloists improvise during the other repetitions. The overall form of verse-like repetition, with the melody played only the first and final times, and improvisations on the other repetitions, is very common in jazz even when the A A B A song form is not being used.
    • Rondo – One section returns repeatedly, with a section of new music before each return. (A B A C A ; sometimes A B A C A B A).

    Learn and Listen: Rondo

    Teoria offers tutorials on the rondo form. Follow these links to learn more:

    Rondo 1

    Rondo 2

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    • Dance forms – Dance forms usually consist of repeated sections (so there is plenty of music to dance to), with each section containing a set number of measures (often four, eight, sixteen, or thirty-two) that fits the dance steps. Some very structured dance forms (Minuet, for example) are associated even with particular phrase structures and harmonic progressions within each section.
    • Binary form – Two different main sections (A B). Commonly in Western classical music, the A section will move away from the tonic, with a strong cadence in another key, and the B section will move back and end strongly in the tonic.

    Learn and Listen: Binary Form

    Teoria offers tutorials on the binary form. Follow these links to learn more:

    Binary 1

    Binary 2

    Binary 3

    Binary Courante

    Binary Air

    • Ternary Form – Three main sections, usually A B A or A B A’.

    Learn and Listen: Ternary Form

    Teoria offers tutorials on the Ternary Form. Follow these links to learn more:

    Ternary 1

    Ternary 2

    Ternary 3

    • Cyclic Form – There are two very different uses of this term. One refers to long multimovement works (a “song cycle”, for example) that have an overarching theme and structure binding them together. It may also refer to a single movement or piece of music with a form based on the constant repetition of a single short section. This may be an exact repetition (ostinato) in one part of the music (for example, the bass line, or the rhythm section), while development, variation, or new melodies occur in other parts. Or it may be a repetition that gradually changes and evolves. This intense-repetition type of cyclic form is very common in folk musics around the world and often finds its way into classical and popular musics, too.
    • Sonata form – may also be called sonata-allegro form. In this form, repetition and development of melodic themes within a framework of expected key changes allow the composer to create a unified long movement.
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