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 labelled 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 labelled A. If it is very much like the A section, but with some important differences, it can be labelled 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 labelled B, and other sections that are like it can be labelled B, B', B", and so on. Sections that are not like A or B are labelled C, and so on.
How do you recognize the sections? With familiar kinds of music, this is pretty easy. (See the below Figure 5.38 for some examples of forms that will be familiar to most listeners.) 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. For an excellent discussion of form, with plenty of chances to practice hearing the beginnings of new sections, please see Professor Brandt's Sound Reasoning course. In particular, Musical Form56 deals with recognizing when something new is being introduced (A/B instead of A only), and Time's Effect on the Material deals with recognizing when a section reappears changed (A', B', or A”).
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.
- 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. (You may want to note the differences - and the similarity - in the use of the term bridge by popular musicians and jazz musicians; see below (Some Common Forms)).
- 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 (Figure 5.39) at the tune of one verse shows that within that overall form is an A A' B A" phrase structure.
Now try labeling the phrases of a verse or a refrain of some of the songs you listened to in Exercise 5.19. Listen for phrases that use similar melodies. (Sometimes, but not always, they even use the same words.) How many of your refrains and verses were basically A A B A? What were the others?