III. Form
Brian Jarvis
Key Takeaways
- Rondo is a form featuring a main section (referred to as either A or ) that returns throughout a work and is juxtaposed with contrasting sections (referred to as B, C, etc., or as ).
- Common formal layouts include ABACA (five-part) and ABACABA (seven-part, likely sonata rondo).
Conceptually, rondo is quite simple: the form consists of a recurring that alternates with . As with other forms, rondo can include a variety of . In rondo form, it is tradition to call the repeating main section the (or A), and the contrasting sections are referred to as (and/or by letters: B, C, etc.).
The refrain material is essentially the same throughout the course of a movement (allowing for some embellishment or abbreviation) and is always heard in the tonic key. Episodes contrast with refrains tonally, and usually thematically as well. A given episode may occur multiple times in the movement or only once.
The most common manifestations of rondo form are either five-part rondo (ABACA) or sonata rondo (ABACABA), summarized in Example 1. There are two main differences between them:
- In sonata rondo, the C section is often akin to a sonata form’s section, whereas in a five-part rondo, the C section is likely to be a relatively stable thematic statement like any other episode.
- In sonata rondo, the first ABA (i.e., ABACABA) constitutes the equivalent of a complete sonata (without the repeat, and it ends in the tonic), and the second ABA (i.e., ABACABA) functions as the , where the B section is now transposed to the tonic key.

Refrains, Episodes, and Auxiliary Sections in Rondo Form
Refrains are constructed as a combination of one or more phrases and could even be an entire . You can expect that they will have a clear ending punctuated with a and will be relatively stable thematic statements. Episodes may be structured like that as well (though with contrasting keys and melodic/motivic material), or they can include destabilizing features like , chromatic harmony, and . Episodes may end with a clear PAC, or they may have ambiguous endings, even lacking a cadence and merging into a section instead through the process of .
Like other forms, rondo form can have auxiliary sections. The most common are that generate anticipation for the refrain’s return. are also quite common, but are not.
Analytical Challenges with Episodes: Transition ⇒ Episode or Episode ⇒ Retransition
Like the other forms, rondos may include any combination of auxiliary sections, though retransitions that dramatize the return of the refrain are particularly common. Since episodes are often relatively looser than their refrain counterparts, two sections may blend together through the . In particular, a transition may become an episode without any clear delineation of the two formal sections. Similarly, the episode itself may not reach a clear cadential conclusion (i.e., a PAC in the key of the episode) and instead may become a retransition that prepares for the statement of another refrain. However, it is unlikely to find both of these situations occurring within a single episode. One of the important distinctions between the end of a connective section (transition/retransition) and a stable thematic statement (refrains and episodes) is that connective sections tend to emphasize their arrival on the dominant, while stable thematic statements tend to emphasize the arrival at a PAC.
Five-Part Rondo Example
Example 2. Maria Hester Park, Piano Sonata in C major, Op. 7, 3rd movement – Audio (YouTube) – Click to See Score (PDF)
The final movement from Maria Hester Park’s Sonata in C major, Op. 7, from 1796 is a relatively clear example of a five-part rondo form. The A section () lasts from mm. 1–26 and consists of multiple phrases. The B section (episode 1) does not start right away at m. 27; it is instead separated from A by a (mm. 27–44) that modulates to the key of the dominant in m. 38 during a passage of chromaticism involving modal mixture. Unlike most transitions, this transition actually ends on the upcoming local tonic of G major (mm. 42–44) instead of the local dominant. B‘s primary thematic material lasts from mm. 45–54, and its ending is elided with a suffix that eventually becomes a retransition (around m. 71) that harmonically prepares for the return of A in m. 73. This second statement of A lasts from mm. 73–98 and is a complete repeat of the first statement of A. C (episode 2) starts in m. 99, immediately after the second statement of A, and is in a contrasting key, the submediant (A minor). The C section (mm. 99–132) is longer than the B section. Its ending elides with the start of a that becomes a (around m. 135). The third and final statement of A starts in m. 141 and is again a complete repeat of the initial statement of A.
Sonata Rondo Example
Example 3. Ludwig van Beethoven, Piano Sonata in C minor, Op. 13, 3rd movement – Click to See Score (PDF)
The A Sections (Refrains)
The last movement from Beethoven’s Op. 13 piano sonata (subtitled Grande Sonate pathétique) is an example of a sonata-rondo form. The form is fairly complex, and while most of the sections are quite clear, the B section in particular has a few challenges. The form also includes a good amount of . When approaching the form of any rondo, an efficient strategy for determining the form is to find the location of the A sections. Remember that restatements of A need to be in the tonic key and that they may contain slight variations like omitted repeats, melodic embellishments, and/or new accompaniments. In this particular form, the A sections can be found starting in mm. 1, 62, 121, and 171.
In order to understand the differences between the A sections, a more detailed look at the structure of the initial A section is required. The initial A section ends in m. 17, and there are two techniques used to generate that length. The first is the that starts in m. 9 (mm. 9–12 are a varied repetition of mm. 5–8). The second expansion technique is the that starts in m. 12. This suffix starts with an and ends in m. 17. So, what could have been an 8-measure theme is now 17 measures because of these two expansion techniques.
With that more detailed analysis in mind, we now have a model we can use to compare the other A sections. While the second A section is a repeat of the first, the third and fourth A sections have been altered. The third A section is the shortest, lasting only 8 measures. It achieves this brevity by removing both of the expansion techniques used in the A section’s initial statement. Instead of having the one-more-time technique in its ninth measure, new, unstable music enters that is derived from the A section but is used as the start of a transition away from the A section’s material. The fourth and last A section ends at measure 182, making it 12 measures long. In this version, the one-more-time repetition is still included, but A‘s original suffix has been replaced by a new, much longer suffix that functions as the work’s (mm. 183–210).
The B sections (Episodes 1 & 3)
This movement’s episodes vary in key and melodic/motivic material, and they contain multiple auxiliary sections including , , and suffixes. The first episode, B, is the most complex, and it is stated twice throughout the work. As is expected for sonata-rondo form, the first statement of B is in a contrasting key (the mediant) and its restatement in the “recapitulation” is in the tonic key of C—though instead of being in the minor mode to match the global key, it is in the parallel major key of C major (I).
While it’s very clear that the initial B section occurs somewhere between the first two A sections (mm. 18–62), the initiation of B is obscured by a number of features, resulting in an ambiguous starting point. There are four possible candidates for the beginning of B: mm. 25, 33, 37, and 44. There is certainly a transition starting in m. 18 due to the harmonic/melodic sequence and harmonic instability, but m. 25’s relatively stable presentation of melodic material is obscured by the lack of separation between the rhythmic activity leading into it and the fact the this melodic/motivic material is not new—it’s derived from the A section’s suffix (see m. 12)—obscuring a possible initiation function. The next candidate, m. 33, is marked because of the dominant arrival and because it introduces new melodic material involving a triplet figure. However, this candidate for the start of B is also obscured by lack of rhythmic separation between mm. 32 & 33 and the fact that m. 33 starts on a dominant harmony instead of the tonic (III). M. 37 is a similarly unclear starting point because it continues the melodic/motivic material introduced in m. 33 instead of introducing its own material, even though it is the first statement of that material in the local tonic of E♭ major. The last candidate is m. 44. Of all the options, this is the clearest starting point because of the textural gap that preceded it. However, it is very uncommon for episodes to start after a PAC has been sounded in the local key, which is the case here (see m. 43). Typically a suffix would begin after a PAC occurs in the local key of an episode. This is all to say that, after careful consideration, no clear starting point of B can be determined, and yet it seems very clear that the presence of an episode in a contrasting key occurs. In order to avoid making a dubious factual statement about exactly where B starts, I think the best way to capture the reality of this passage is to invoke the concept of . So, while it’s clear that a transition begins in m. 18, the B section has no clear beginning; instead, the transition “becomes” the B section somewhere between mm. 25 and 44 but in no precise location.
The space between B and the second statement of A is a little clearer. The PAC in III at m. 51 marks the end of B and the simultaneous start of a suffix. As is common in many forms, this suffix turns into a connective section (in this case a retransition) without a clear division between the two sections, again achieving this fluidity through the process of becoming. The dominant arrival in the global key at m. 58 is a common marker of being in a retransition.
When the B section returns in the recapitulation, it is approached with a newly composed transition (m. 129). The return of B‘s material starts around mm. 134–135 (compare with mm. 25–26). Similar to the exposition’s B section, the exact location of the initiation of B in the recapitulation is also obscured. In the recapitulation, B‘s original suffix (m. 51) is omitted; instead, the melodic/motivic material first stated in m. 44 is recomposed in the recapitulation so that it now blends into a new retransition through the process of becoming before it leads to the final statement of A in m. 171.
The C Section (Episode 2)
In this movement, the C section is much easier to identify than the B sections were. It features a very clear beginning in m. 79 (notice also the clear separation of the end of A in the previous measure) and begins in the contrasting key of the submediant (A♭ major). The internal form of this section could be considered a rounded binary form in which the returning A section is not complete and instead becomes a retransition. The internal A section features a modulating period (mm. 79–86) with a written-out repeat to accommodate some textural changes (mm. 87–94). The internal B section is short (mm. 95–98), and the return of the internal A (m. 99) introduces a new texture, but the consequent phrase does not close; instead, it becomes a retransition around m. 104 that reaches a strong dominant arrival (m. 107), featuring a dramatic preparation for the return of A at m. 121. Though many sonata-rondo forms contain a C section akin to a sonata form’s development section, this movement does not, and C is instead a clear statement of an episode in a contrasting key that leads to a retransition.
Media Attributions
- rondo-combined
In a rondo form, a refrain refers to the work's primary theme. It is often referred to as a refrain because of its recurrent nature. In most rondos, the refrain is stated at the beginning, restated after each contrasting episode, and then one more time as the last form sectional, though a coda may follow.
A term used when describing the sections of a rondo form that are not the main theme (a.k.a. A or refrain). Episodes provide contrast with the main theme through changes in multiple domains, primarily key and melodic/rhythmic/harmonic material.
A section that presents the work's primary musical ideas. Usually, the main section is the first core section of the work. Examples include primary themes, refrains, expositions, choruses, or strophes.
A core section that provides contrast with the main section. May be stable or unstable.
Sections that introduce, follow, or come between a work's core sections (A, B, primary & secondary themes, refrains, episodes, and developments/digressions/contrasting middles). Auxiliary sections are either external or internal. External Auxiliary Sections either introduce a piece/section (prefix) or follow the piece's/section's generic conclusion (suffix). Prefixes and suffixes come in small and large varieties. Internal auxiliary sections (connective sections) function to connect two core sections. Transitions generally help lead away from the piece's main section toward a contrasting section (B, secondary theme, episodes, developments/digressions/contrasting middles), and retransitions generally help to lead back to the piece's main section (usually A or a sonata form’s primary theme).
A section of a sonata form that is unstable, and which may or may not explore thematic material established in the exposition.
The first large section in a sonata form work. It usually establishes the main themes of a work and sets up a conflict that is later resolved in the work. This conflict often takes the form of differing key centers (such as when the primary theme of a sonata is in tonic and the secondary theme is in the dominant)
A section of a sonata form work that beings back themes from the exposition and which resolves the conflict established in the exposition.
In the context of musical form, the term binary means a formal type that has two main parts often called reprises because each main part is typically repeated. There are three types of binary form: rounded, balanced, and simple. Binary forms are common in the 17th, 18th, and 19th centuries and they were used heavily in dance music. Binary form is typically one of the shorter forms and because of that, they are often embedded within larger, compound, forms like compound ternary form.
A V-I cadence in which both harmonies are in root position and in which Do (scale-degree 1) is in the soprano over the tonic chord.
A change of key.
In the Classical-era of western, classical music—which spans the middle to the end of the 18th century—there were a specific set of standard modulation schemes that were used within a section of music. These are summarized below:
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The lengthening of a phrase, whether internally or externally, beyond its expected duration resulting from a "play" with grouping units.“Expected duration” is defined contextually, and it may rely on such factors as: era, genre, pre-established models (i.e., projection) “Play” may occur either within a single group (stretching) or by stringing together additional groups (adding). Stretching and Adding can also occur at the same time.
A retransition is very similar to a transition but its location and function are different. Retransitions come between two sections where the upcoming section is the initiation of a large-scale return. In most cases, retransitions help prepare the return of the piece’s main section. In a ternary form this would be the A section, in a sonata form this would be the restatement of the primary theme at the onset of the recapitulation, and in a rondo this would be the return of the refrain (a.k.a. the A section). A retransition often drives toward attaining the dominant chord of the home key and will often prolong the dominant once attained, usually in the form of a suffix. Retransitions may have a clear half-cadential ending (possibly followed by a suffix), or they may have an elided ending that coincides with the initiation of the following section.
The process of becoming is an analytical phenomenon that captures an in-time, analytical reinterpretation regarding a formal/phrasal unit's function. In this situation, a formal/phrasal label at first seemed fitting, but as that unit continues in time, a different label seems fitting. Even upon re-listening, this process of conversion is likely to still be experienced. The rightwards-double arrow symbol (⇒) is often used to denote this process. Examples include, primary theme ⇒ transition, continuation ⇒ cadential, suffix ⇒ transition, and any number of other combinations.
A coda is a song-ending section that presents new material. Like outros, codas exhibit closing rhetoric.
A section of music that occurs before the start of the musical form proper. In faster movements, introductions tend to have noticeably slower tempi. Introduction can range considerably in length, ranging from less than a single phrase (small prefix) to one or more phrases (large prefix). In the 18th century, introductions often contained independent musical material that doesn't appear in the rest of the work proper, but in the 19th century, composers tended to explore the integration of the introduction's material with the rest of the work.
Generally, a section of music that functions to connect two thematic sections. In particular, a transition comes between two sections where the upcoming section is not the initiation of a large-scale return (e.g., transitions are commonly found between an A and B sections, or between the Primary and Secondary themes in a sonata). Transitions usually help to lead away from the piece's main section toward a contrasting section. Often a modulation is introduced to help prepare a section in a new key, though a modulation is not required. Transitions are a type of auxiliary section and they come in small and large varieties. Large transitions contain at least one complete phrase and small transitions don't contain complete phrases.
A type of external expansion that occurs after the end of a phrase. There are three terms we commonly use to describe suffixes, ranging in size from smaller to larger: post-cadential extension, codetta, and coda.
An elision is the overlapping of two phrases that functions as the ending of one phrase and the simultaneous beginning of the next.
A type of suffix (external auxiliary section). Codas are usually of the large variety (a phrase or longer), and they occur at the end of a work (or end of a movement within a multi-movement work) after the PAC that ends the piece proper. The word coda is Italian for “tail” because they are found at the tail end of a work. Sometimes composers communicate the location of the coda by writing the word in the score but this is not necessary to identify a section as a coda. Like all suffixes, codas are considered an expansion technique and therefore the are not essentially to the structural content of the work and it is often said that the work would still make complete syntactic sense if it were removed entirely.