Sonata form is a musical form that has been used widely since the early Classical period. It has typically been used in the first movement of multimovement pieces, and is therefore more specifically referred to as sonata-allegro form or first-movement form. Study of the sonata form in music theory rests on a standard definition, and a series of hypotheses about the underlying reasons for the durability and variety of the form.
The standard definition focuses on the thematic and harmonic organization of tonal materials, which are presented in an exposition, elaborated and contrasted in a development and then resolved harmonically and thematically in a recapitulation. Additionally the standard definition recognizes that an introduction and a coda may be present. Each of the sections is often further divided or characterized by the particular means by which it accomplishes its function in the form.
The sonata form, since its establishment, became the most common form in the first movement of works entitled "sonata", as well as other long works of classical music, including symphonies, string quartets and Tone Poems. Accordingly there is a large body of theory on what unifies and distinguishes practice in the sonata form, both within eras, and between eras. Even works which do not adhere to the standard description of a sonata form, often present analogous structures, or are meant to be elaborations or expansions on the standard description.
Although the term sonata often refers to a piece in sonata form, it is essential to separate the two. As the title for a single-movement piece of instrumental music (from the Italian "sonare", to sound (of an instrument), opposed to the cantata, from "cantare" meaning to sing), "sonata" covers many pieces from the Baroque and mid-18th century that are not "in sonata form". Conversely, in the late 18th century or "Classical" period, the title "sonata" is typically given to a work composed of three or four movements. Nonetheless, this multi-movement sequence is not what is meant by sonata form, which refers to the structure of an individual movement.
The definition of sonata form in terms of musical elements sits uneasily between two historical eras. Although the late 18th century witnessed the most exemplary achievements in the form, above all from Joseph Haydn and Wolfgang Amadeus Mozart, compositional theory of the time did not use the term "sonata form". The most extensive contemporary description of the sonata-form type of movement was given by the theorist H. C. Koch in 1793: like earlier German theorists, and unlike the descriptions of the form we are used to today, he defined it in terms of the movement's plan of modulation and principal cadences, without saying a great deal about the treatment of themes. Seen in this way, sonata form was closest to binary form, out of which it developed. The model of the form that is usually taught currently is more thematically differentiated. It was originally promulgated by Antonin Reicha in Traité de haute composition musicale in 1826, by Adolph Bernhard Marx in Die Lehre von der musikalichen Komosition in 1845, and by Carl Czerny in 1848. Marx is the originator of the term "sonata form".
This model was derived from study and criticism of Beethoven's piano sonatas; however, coming as it did after Beethoven's death, and long after the heyday of the form as used by composers, it already had a slightly abstract and retrospective character. Since it still has wide currency and provides the theorist with a range of indispensable analytical terms. Therefore before the larger arguments over sonata form can be considered, it demands summary.
It may begin with an introduction, which is generally slower than the main movement. Introductions are structurally an upbeat before the main musical argument.
The first required section is the exposition. The exposition presents the primary thematic material for the movement: one or two theme groups, often in contrasting styles and in opposing keys, bridged by a transition. The exposition typically concludes with a closing theme, a codetta, or both.
The development then transitions to the recapitulation where the thematic material returns in the tonic key, and for the recapitulation to complete the musical argument, material which has not been stated in the tonic key is "resolved" by being played, in whole or in part, in the tonic.
The term 'sonata form' is controversial and has been called misleading by scholars and composers almost from its inception. Its originators implied that there was a set template to which Classical and Romantic composers aspired, or should aspire to.
However, the 'sonata form' is presently often viewed a model for musical analysis, rather than for compositional practice. Although the descriptions on this page could be considered an adequate analysis of many first-movement structures, there are enough variations that theorists such as Charles Rosen have felt them to warrant the plural in 'Sonata forms.'
In the Classical era, these variations include, but are not limited to, a monothematic exposition, where the same material is presented in different keys, used extensively by Haydn, a 'third subject group' in a different key to the other two, used by Schubert and Brahms, the second subject group recapitulation in the 'wrong' key, often the subdominant, as in Mozart's C major piano sonata KV. 545, and Schubert's third symphony, and an extended coda section that pursue typically developmental, rather than concluding, processes. This is found in most of Beethoven's middle-period works, such as his third symphony.
Through the Romantic period, formal distortions and variations become so widespread (Mahler, Elgar and Sibelius among others are cited and studied by James Hepokoski) that 'sonata form' as it is outlined here is not adequate to describe the complex musical structures that it is often applied to.
In the context of the many late Baroque extended binary forms that bear similarities to sonata form, sonata form can be distinguished by the following three characteristics:
The standard description of the sonata form is:
Occasionally the material of introduction reappears in its original tempo later in the movement. Often, this occurs as late as the coda, as in Mozart's String Quintet K. 593, Haydn's Drumroll Symphony, or Beethoven's Piano Sonata No. 8 ("Pathétique").
The development varies greatly in length from piece to piece, sometimes being relatively short compared to the exposition (e.g. the first movement of Eine kleine Nachtmusik, K 525/I by Mozart) and in other cases quite long and detailed (e.g. the first movement of the "Eroica" Symphony by Beethoven). However, it almost always shows a greater degree of tonal, harmonic and rhythmic instability than the other sections. At the end, the music will return to the dominant key in preparation of the recapitulation. The transition from the development to the recapitulation is a crucial moment in the work.
The last part of the development section is called the retransition: it prepares for the return of the first subject group in the tonic, most often through a grand prolongation of the dominant seventh. Thus, if the key of the movement is C major, the retransition would most typically stress the dominant seventh chord on G. In addition, the character of the music would signal such a return, often becoming more frenetic (as in the case of the first movement of Beethoven's "Waldstein" Sonata, Op. 53). A rather notable exception to the harmonic norm of the retransition occurs in the first movement of Brahms's Piano Sonata No. 1, Op. 1. The general key of the movement is C major, and it would then follow that the retransition should stress the dominant seventh chord on G. Instead, it builds in strength over the seventh chord on C, as if the music were proceeding to F major. At the height of the musical tension, this chord triumphs with great volume and wide registral scope on the downbeat, only to take up immediately the first theme in C major – that is, without any standard harmonic preparation.
It is not necessarily the case that the move to the dominant key in the exposition is marked by a new theme. Haydn in particular was fond of using the opening theme, often in a truncated or otherwise altered form, to announce the move to the dominant. Mozart, despite his prodigious melodic gift, also occasionally wrote such expositions: for instance in the Piano Sonata K. 570 or the String Quintet K. 593. Such expositions are often called monothematic, meaning that one theme serves to establish the opposition between tonic and dominant keys. This term is misleading, since most "monothematic" works have multiple themes: most works so labeled have additional themes in the second subject group. Only on occasion (for example, in Haydn's String Quartet Op. 50 no. 1) did composers perform the tour de force of writing a complete sonata exposition with just one theme. A more recent example is Edmund Rubbra's 2nd Symphony.
The fact that so-called monothematic expositions usually have additional themes is used by Charles Rosen to illustrate his theory that the Classical sonata form's crucial element is some sort of dramatisation of the arrival of the dominant. Using a new theme was a very common way to achieve this, but other resources such as changes in texture, salient cadences and so on were also accepted practice.
The key of the second subject may be something other than the dominant or the relative major (or relative minor). About halfway through his career, Beethoven began to experiment with other tonal relationships between the tonic and the second subject group. Most commonly, both in Beethoven and other composers, the mediant or submediant, rather than the dominant, is used for the second group. For instance, the first movement of the "Waldstein" sonata, in C major, modulates to the mediant E major, while the opening movement of the "Hammerklavier" sonata, in B-flat major, modulates to the submediant G major.
The exposition need not only have two key areas. Some composers, most notably Schubert, composed sonata forms with three or more key areas. The first movement of Schubert's Quartet in D minor, D. 810 ("Death and the Maiden"), for example, has three separate key and thematic areas, in D minor, F major, and A minor.
An important variant on traditional sonata-allegro form is found in the first movement of the Classical concerto. Here, the sonata-allegro's customary 'repeated exposition' is replaced by two different but related sections: the 'tutti exposition' and the 'solo exposition'. In the tutti exposition, the orchestra alone will normally expose all or most of the movement's themes, but without any modulation to a second subject key; this modulation will be reserved for the following solo exposition, in which the soloist will feature. This arrangement can be seen as a combination of the structural and expressive possibilities of sonata form with elements of Classical concerto's ritornello form predecessor.
A structural feature which the special textural situation of the concerto makes possible is the 'ownership' of certain themes or materials by the solo instrument; such materials will thus not be exposed until the 'solo' exposition. Mozart was fond of deploying his themes in this way.
Towards the end of the recapitulation of a concerto movement in sonata form, there is usually a cadenza for the soloist alone. This has an improvisatory character (it may or may not actually be improvised), and generally serves to prolong the harmonic tension on a dominant-quality chord before the orchestra ends the piece in the tonic.
The term sonata is first found in the 17th century, when instrumental music had just begun to separate itself from vocal music. Originally the term (derived from the Italian word suonare, to sound on instrument) meant a piece for playing, distinguished from cantata, a piece for singing. At this time the term implies a binary form, usually AABB with some aspects of three part forms.
The Classical era established the norms of structuring first movements and the standard layouts of multi-movement works. There was a period of a wide variety of layouts and formal structures within first movements which gradually became expected norms of composition. The practice of Haydn and Mozart, as well as other notable composers, became increasingly influential on a generation which sought to exploit the possibilities offered by the forms which Haydn and Mozart had established in their works. Gradually theory on the layout of the first movement became more and more focused on understanding the practice of Haydn, Mozart and, later, Beethoven. Their works were studied, patterns and exceptions to those patterns identified, and the boundaries of acceptable or usual practice set by the understanding of their works. The sonata form as it is described is strongly identified with the norms of the Classical period in music. Even before it had been described the form had become central to music making, absorbing or altering other formal schemas for works.
The Romantic era in music was to accept the centrality of this practice, codify the form explicitly and make instrumental music in this form central to concert and chamber composition and practice, particularly for works which were meant to be regarded as "serious" works of music. Various controversies in the 19th century would center on exactly what the implications of "development" and sonata practice actually meant, and what the role of the Classical masters was in music. Ironically, at the same time that the form was being codified (by the likes of Czerny and so forth), composers of the day were writing works that flagrantly violated some of the principles of the codified form.
It has continued to be influential through the subsequent history of classical music through to the modern period. The 20th century brought a wealth of scholarship that sought to found the theory of the sonata form on basic tonal laws. The 20th century would see a continued expansion of acceptable practice, leading to the formulation of ideas that there existed a "sonata principle" or "sonata idea" which unified works of the type, even if they did not explicitly mean the demands of the normative description.
Sonata form shares characteristics with both binary form and ternary form. In terms of key relationships, it is very like binary form, with a first half moving from the home key to the dominant and the second half moving back again (this is why sonata form is sometimes known as compound binary form); in other ways it is very like ternary form, being divided into three sections, the first (exposition) of a particular character, the second (development) in contrast to it, the third section (recapitulation) the same as the first.
The early binary sonatas by Domenico Scarlatti provide excellent examples of the transition from binary to sonata-allegro form. Among the many sonatas are numerous examples of the true sonata form being crafted into place. During the 18th century many other composers like Scarlatti were discovering this same musical form by experimenting at their keyboards harmonically and melodically.
The sonata form is a guide to composers as to the schematic for their works, for interpreters to understand the grammar and meaning of a work, and for listeners to understand the significance of musical events. A host of musical details are determined by the harmonic meaning of a particular note, chord or phrase. The sonata form, because it describes the shape and hierarchy of a movement, tells performers what to emphasize and how to shape phrases of music. Its theory begins with the description, in the 1700s, of schematics for works, and was codified in the early 19th century. This codified form is still used in the pedagogy of the sonata form.
In the 20th century, emphasis moved from the study of themes and keys to how harmony changed through the course of a work and the importance of cadences and transitions in establishing a sense of "closeness" and "distance in a sonata". The work of Heinrich Schenker and his ideas about "foreground", "middleground" and "background" became enormously influential in the teaching of composition and interpretation. Schenker believed that inevitability was the key hallmark of a successful composer, and that therefore works in sonata form should demonstrate an inevitable logic.
In the simplest example, playing of a cadence should be in relationship to the importance of that cadence in the overall form of the work. More important cadences are emphasized by pauses, dynamics, sustaining and so on. False or deceptive cadences are given some of the characteristics of a real cadence, and then this impression is undercut by going forward more quickly. For this reason changes in performance practice bring changes to the understanding of the relative importance of various aspects of the sonata form. In the Classical era, the importance of sections and cadences and underlying harmonic progressions gives way to an emphasis on themes. The clarity of strongly differentiated major and minor sections gives way to a more equivocal sense of key and mode. These changes produce changes in performance practice: when sections are clear, then there is less need to emphasize the points of articulation. When they are less clear, greater importance is placed on varying the tempo during the course of the music to give "shape" to the music.
Over the last half-century a critical tradition of examining scores, autographs, annotations and the historical record has changed, sometimes subtly, occasionally dramatically, the way the sonata form is viewed. It has led to changes in how works are edited; for example, the phrasing of Beethoven's piano works has undergone a shift to longer and longer phrases which are not always in step with the cadences and other formal markers of the sections of the underlying form. Compare the recordings of Schnabel, from the beginning of modern recording, with those of Barenboim and then Pratt shows a distinct shift in how the structure of the sonata form is presented to the listener over time.
For composers, the sonata form is like the plot of a play or movie script, describing when the crucial plot points are, and the kinds of material that should be used to connect them into a coherent and orderly whole. At different times the sonata form has been taken to be quite rigid, and at other times a freer interpretation has been generally considered permissible.
In the theory of sonata form it is often asserted that other movements stand in relation to the sonata-allegro form, either, per Charles Rosen that they are really "sonata forms", plural - or as Edward T. Cone asserts, that the sonata-allegro is the ideal to which other movement structures "aspire". This is particularly seen to be the case with other movement forms which commonly occur in works thought of as sonatas. As a sign of this the word "sonata" is sometimes prepended to the name of the form, particularly in the case of the "sonata-rondo" form. Slow movements, in particular, are seen as being similar to sonata-allegro form, with differences in phrasing and less emphasis on the development.
Conversely Schoenberg and other theorists who used his ideas as a point of departure see the theme and variations as having an underlying role in the construction of formal music, calling the process continuing variation, and argue from this idea that the sonata-allegro form is a means of structuring the continuing variation process. Theorists of this school include Erwin Ratz and William E. Caplin.
Subsections of works are sometimes analyzed as being in sonata form, particularly single movement works, such as the Konzertstück in F minor of Carl Maria von Weber.
From the 1950s onwards, Hans Keller developed a 'two-dimensional' method of analysis which explicitly considered form and structure from the point of view of listener expectations. In his work, Sonata-Allegro was a well-implied 'background form' against whose various detailed features composers could compose their individual 'foregrounds'; the 'meaningful contradiction' of expected background by unexpected foreground was seen as generating the expressive content. In Keller's writings this model is applied in detail to Schoenberg's 12-note works as well as the classical tonal repertoire. Recently two other musicologists, James Hepokoski and Warren Darcy, have presented (without reference to Keller) an analysis of the Sonata-Allegro form and the Sonata Cycle in terms of genre expectations, and categorized both the sonata-allegro movement and the sonata cycle by the compositional choices made to respect or depart from conventions. Their study focuses on the normative period of sonata practice, namely the works of Haydn, Mozart, Beethoven, Schubert, and their close contemporaries, projecting this practice forward to development of the sonata-allegro form into the 19th and 20th centuries.