A parallel period is a musical structure that consists of two phrases, both of which begin with the same or similar material. This creates a sense of repetition and unity between the two phrases. In this article, we’ll explore what a parallel period is in music theory and how it’s used in compositions.

Structure of a Parallel Period

A parallel period typically consists of two phrases, each containing two subphrases. The first subphrase of each phrase is usually identical or similar, while the second subphrase differs in some way. This creates a sense of contrast between the two phrases.

Let’s look at an example to illustrate this structure:

In this example, both phrases begin with the same subphrase (C-G-C) but have different second subphrases (D-F-A and E-G-B). This creates a sense of repetition and unity between the two phrases while also providing contrast.

Uses of Parallel Periods in Music Theory

Parallel periods are commonly used in music to create a sense of structure and coherence within a composition. By repeating material between phrases, composers can create a sense of familiarity for listeners while also introducing new material to keep things interesting.

Parallel periods are often used in classical music, particularly in sonata form movements. In these compositions, the first theme is typically presented in a parallel period structure before moving on to other themes.

Parallel periods are also used in popular music. For example, many pop songs use a verse-chorus structure, with the chorus typically being a parallel period that repeats throughout the song.

Conclusion

In conclusion, a parallel period is a musical structure that consists of two phrases, both of which begin with the same or similar material. Parallel periods are commonly used in music to create structure and coherence within compositions, and they can be found in both classical and popular music.