Editing History of sonata form (section)

== Romantic period (ca 1800 – ca 1910) ==
[[File:Adolf_Bernhard_Marx.jpg|thumb|Portrait of music theorist [[Adolf Bernhard Marx|Adolph Bernhard Marx]]]]
Ludwig van Beethoven was the composer who most directly inspired the theorists who codified sonata form as a particular practice. While he was grounded in the fluid phrase structures and wider variety of possible schematic layouts that came from Haydn and Mozart, his deepest innovation was to work from both ends of a sonata form, conceiving of the entire structure, and then polishing themes which would support that overarching design. He continued to expand the length and weight of the sonata forms used by Haydn and Mozart, as well as frequently using motives and harmonic models drawn from the two older composers. He shares both the Classical and Romantic eras. Because of his use of increasingly characteristic rhythms and disruptive devices, he is seen as a transitional figure between the Classical and Romantic periods.

In the Romantic era, sonata form was first explicitly defined and became institutionalized.  Academic scholars like [[Adolf Bernhard Marx|Adolph Bernhard Marx]] wrote descriptions of the form, often with a [[normative]] goal; that is, a goal of stating how works in sonata form ''should'' be composed.  While the first-movement form had been the subject of theoretical works, it was seen as the pinnacle of musical technique. Part of the training of 19th-century composers was to write in sonata form and to favor sonata form in the first movement of multi-movement compositions, like symphonies, piano concertos, and string quartets.

The 19th century's procedure for writing sonatas diverged from earlier Classical practice, in that it focused more on [[theme (music)|themes]] than on the placement of [[cadence (music)|cadences]].  The [[monothematic]] exposition (a common characteristic of Haydn's sonata-form movements) largely disappeared, and the themes of the first and second groups were expected to contrast in character.  More generally, the formal outline of a sonata came to be viewed more in terms of its themes or groups of themes, rather than the sharp differentiation of [[key (music)|tonal areas]] based on cadences. In the Classical period, establishing the expectation of a particular cadence and then delaying or avoiding it was a common way of creating tension. In the 19th century, with its dramatically expanded harmonic vocabulary, avoidance of a cadence did not have the same degree of unexpectedness. Instead, more [[distant key]] regions were established by a variety of other means, including use of increasingly [[consonance and dissonance|dissonant]] chords, [[pedal point]]s, [[texture (music)|texture]], and alteration of the main theme itself.

In the Classical period, the contrast between theme groups, while useful, was not required. The first theme group tended to outline the tonic chord, and the second theme tended to be more ''[[cantabile]]'' in character. But this was far from universal – as Haydn's monothematic [[exposition (music)|expositions]] and Beethoven's early rhythmic themes show. Because the power of harmonic opposition, both between [[tonic (music)|tonic]] and [[dominant (music)|dominant]] and between [[major key|major]] and [[minor key|minor]], had less force in the Romantic vocabulary, stereotypes of the character of themes became stronger. Nineteenth-century theorists described the sonata principle as one of opposition between two groups of themes. Thus, it was thought by Marx that the first theme should be "masculine" – strident, rhythmic, and implying a dissonance – and the second theme group should be drawn more from vocal melody making it "feminine".  It is this contrast between "rhythmic" and "singing" that [[Wagner]], in his very influential work ''On Conducting'', argued was at the very core of tension in music. That texture, as Wagner argued, is the most important contrast and that [[tempo]] should be used to emphasize this contrast.<ref>{{Cite book |last=Wagner |first=Richard |title=On Conducting |publisher=The Musical Quarterly |year=1869 |pages=34–35 |language=DE}}</ref> Thus, fast sections were conducted faster and slow sections were conducted slower.

By requiring that harmony move with the themes, 19th-century sonata form imposed a kind of discipline on composers and also allowed audiences to comprehend the music by following the appearance of recognizable melodies. However, the sonata form, as an inherited formal mold, also created a tension for Romantic composers between the desire to combine poetical expression and academic rigor.

Later Romantic commentators and theorists detected a "sonata idea" of increasing formalization. They drew a progression of works from Haydn, through Mozart and Beethoven, whereby more and more movements in a multi-movement work were felt to be in sonata form. These theorists present the theory that originally only first movements were in that form, then later last movements as well (for example Mozart's Prague Symphony), and eventually the "sonata principle" came to extend through an entire work. For example, Beethoven's [[String Quartet No. 8 (Beethoven)|String Quartet Op. 59 No. 2]] was said to have all four movements in sonata form. By this, theorists such as [[Donald Tovey]] meant the academically laid-out sonata form. [[Charles Rosen]] has argued that, properly understood, this was always the case: that real ''sonata forms'' (plural) were always present, though this is not universally agreed on.

As the 19th century progressed, the complexity of sonata form grew, as new ways of moving through the harmony of a work were introduced by [[Johannes Brahms]] and [[Franz Liszt]]. Instead of focusing exclusively on keys closely related in the circle of fifths, they used movement along circles based on minor or major [[triad (music)|triads]]. Following the trend established by Beethoven, the focus moved more and more to the development section. This was in line with the Romantic comparison of music to poetry. Poetic terms, such as "[[Rhapsody (music)|rhapsody]]" and "[[tone poem]]", entered music, and increasingly musicians felt that they should not take the repeats in symphonies because there was no dramatic or lyrical point to doing so. This changed their interpretation of previous sonata forms.

The Romantic sonata form was an especially congenial mold for Brahms, who felt a strong affinity with the composers of the Classical era. Brahms adopted and extended Beethoven's practice of modulating to more remote keys in the exposition, combining this with the use of [[counterpoint]] in the inner voices. For example, his [[Piano Quintet (Brahms)|piano quintet]] has the first subject in F minor, but the second subject is in C sharp minor, an [[interval (music)|augmented fifth]] higher. In the same work, the key scheme of the recapitulation is also altered – the second subject in the recapitulation is in F sharp minor, rather than the F minor of the first subject.

Another force acting on sonata form was the school of composers centering on Franz Liszt and Richard Wagner. They sought to integrate more roving harmonies and unprepared chords into the musical structure in order to attain both formal coherence and a full, expressive range of keys. Increasingly, themes began to have notes which were far from the original key, a procedure later labeled "[[extended tonality]]". This trend strongly influenced the next generation of composers, for instance [[Gustav Mahler]]. The first movements of several of his symphonies are described as being in sonata form, although they diverge from the standard scheme quite dramatically. Some{{who|date=November 2012}} have even argued that the entirety of his [[Symphony No. 1 (Mahler)|first symphony]] (in which material from the first movement returns in the fourth movement) is meant to be one massive sonata-allegro form.

As the result of these innovations, works became more sectional. Composers such as Liszt and [[Anton Bruckner]] even began to include explicit pauses in works between sections. The length of sonata movements grew starting in the 1830s. [[Franz Lachner ]]'s ''Prize Symphony'', a work seldom played today, had a first movement longer than any symphonic first movement by Beethoven. The length of whole works also increased correspondingly. Tone poems, which were often in sonata form, greatly extended their length in comparison to traditional overtures. For instance, [[Hector Berlioz|Berlioz]]'s ''Waverley'' Overture is as long as some middle-period Haydn symphonies.

One debate in the 19th century was over whether it was acceptable to use the layout of a poem or other literary work to structure a work of instrumental music. The compositional school focused around Liszt and Wagner (the so-called [[New German School]]) argued in favor of literary inspiration (see [[Program music]]), while another camp, centered on [[Robert Schumann|Schumann]], Brahms, and [[Eduard Hanslick]] argued that [[absolute music|pure music]] should follow the forms laid out by Haydn, Mozart, and Beethoven. This conflict was eventually internalized, and by 1900, though the debate still raged, composers such as [[Richard Strauss]] would freely combine programmatic and symphonic structure, such as in the work ''[[Ein Heldenleben]]''.