Basic Sonata Theory: A Dissertation

From Young Composers
Jump to: navigation, search
Lock.png This is a personally authored article.
This article may be attributed to a specific author; making edits or additions may not necessarily be appropriate.
An essay by Anant Balijepalli

A sonata is a literary form at heart. In classical literature, there are two characters that are introduced. Two very different characters are best introduced in order to create tension. Tension is what is used to create interest. Why would people want to listen to your music if there is no interest? Exactly; the tension is necessary to capture a listener's attention. Now, these characters are developed through a plot. There are many surprises and you learn the history behind the characters until you get to a point in the story where there is a climax of the conflict. The main problem of the story must be resolved so the characters can be on their merry way. After this comes the falling action and the ending or resolution.

Here's where music comes in: Sonata form is essentially this literature form. Theme A and Theme B within the exposition are supposed to be as different as humanly possible. In my piano trio, theme A is solely in dotted notes and has many interval jumps while theme B is smooth. Then, these themes are modified and developed in the development section, but to increase the tension and create surprise, they are put through many different keys (tonal regions). It is important to not return to the tonic at all during the development section due to the fact that your job is to create unresolved tension during the development. Finally, there is a recapitulation in which the themes are shown to be similar and there is a coda (happy ending.. maybe).

Basic structure: Exposition (A-bridge-B), Development (C'x), False Recapitulation (D), Development, Recapitulation (A-newbridge-Btheme in A region), Coda (D)

(I will be using Roman numerals to denote chords of a region) Now comes the more specific stuff:

Part I. — Harmonic relations


Theme A is in the tonic of whatever key you are in. Theme B is usually in the dominant. The dominant modulation involves a II chord or a #IV chord usually. In both of these cases, you are breaking a strong progression (circle progression) and borrowing chords from the Dominant region. For example, II doesn't exist in the tonic region, but when modulating, you are essentially doing a "fake authentic cadence". The I chord in the tonic region is the same as the IV chord in dominant region (i.e. G chord in G major is the same as G chord in D major, which is the subdominant). Both of these modulations help to build energy in an exposition. It is essential, though, that this energy is preserved by avoiding a perfect authentic cadence in the tonic region. In essence, these perfect authentic cadences are markers for the various parts of a sonata.

Instead of moving to the dominant region, though, most Romantic composers moved to the subdominant region instead. The modulation to this region is almost always seen as a reduction of tension. Now, you may be asking yourself: "Why am I reducing tension when I want to get the listener involved?" . Lol. The answer to that comes later. So yeah, common modulations involve a I7 chord in the tonic region. This is the same as a V7 in the subdominant region, so it's a very strong modulation, but because the I7 chord is still (the majority: G, B, D in G major) in the tonic region, it is not as surprising and does not gain as much energy.

Remember: The most important chords in the definition of a region are the IV and V chords. I is not necessary in defining a region.


The start of the development can be in any key you want it to be as long as it is NOT in the tonic region. The most important and most difficult thing in the development region is the lack of a resolutory perfect authentic cadence (especially the feminine kind). A masculine cadence is always preferred since you can phrase link and bring continuity, which is what the development is about. The development should have harmonic tension as well as thematic tension. Say you start in G major, add tension by direct modulation down a semitone (F# minor). The listener will be shocked because there is no real preparation for such a modulation and it will bring tension to the music. Do not return to the tonic at all during this part.

Something that I've found is that the more distant and unprepared a modulation is, the more thematic material can be varied because there is less rooting in previous music. The order and choice of regions is entirely up to the composer. And as Gardener pointed out earlier, certain regions produce certain timbres. Sometimes even these regions can be used for symbolic effect (Like in my Piano Concerto's 2nd movement, the B section is in Ab minor... a key not commonly approached, but has a deep timbre on brass and strings in my opinion. It also has a dark meaning for me).

Within the development, there can be (structurally) a false recapitulation as pointed out above. This can be in any key, but it has traditionally been in the subdominant region. There aren't many rules associated with this besides the fact that you need to keep it varied... don't just repeat your entire exposition.

The most important part of the sonata, though, is the climax section. This occurs in different places depending on the era. In early classical, where the focus was on exposition, the climax MAY have occurred in the exposition itself. As music progressed, the climax shifted to near the end of the development section. The climax is denoted by this: A possibly distant tonal region from the tonic and a climax of the conflicting themes. It is both harmonic and melodic. For example, in my Piano Concerto's first movement, the climax is in Bb minor, which is arguably the farthest one could possibly get from A minor. But although the climax can be harmonic in nature (due to a distant tonal region), it can also be purely melodic with a juxtaposition of themes.

Traditionally (and effectively) in order to lead back into the tonic region for Recapitulation, a pedal note in the bass (on the dominant of the tonic region) is used. For example, in G major, when recapitulating, a D is used to signal a release of tension back to the Tonic.


Almost your ENTIRE exposition is repeated in the TONIC region. Theme A must be left unchanged. The first thing that must be changed is your bridge. I haven't explained this earlier, but the bridge is the place in which your modulation takes place in the exposition. It may have a modification of Theme A, or it may be a completely new theme (see Beethoven's sonata 29, Sonata movement). In the recapitulation, though, the bridge must be re-written because no modulation occurs. What I did in my Piano Trio was to take the piano as a solo instrument and use a sequenced motif in order to create a bridge. Anyway, The B theme (which was originally in either the dominant of Theme A (major mode) or the Submediant of Theme A (minor mode)) must now be in the same MODE and REGION as theme A.

After this recapitulation, there is usually some sort of thematic development of a non-functional type. The bridge theme, for example, can be developed more in the lead up to the coda.


Now generally, this is the bombastic section where the orchestra plays V - I - V - I - V - I in a seemingly endless pattern, BUT it doesn't have to be that way. A coda can move into a completely different harmonic region if it wants to (See Beethoven's 3rd Symphony, Sonata movement.. the coda is played in G major, then finishing on Eb, the tonic). This is where closure must occur in classical sense. Of course, if you don't want the audience member to feel like their journey is over, then use a ton of imperfect cadences and modulation. That'll screw them up =P! But yeah, in keeping with symmetry, Sonata movements usually END in the tonic region.

Part II. — Themes and melody

In the previous section, I talked about the harmonic basis behind the sonata. This harmonic basis helps to explain why sonata form is so effective in capturing people's attention and the literary-structural basis behind the sonata. However, music isn't solely about the harmony. It contains those memorable and sweeping melodies that remain in our minds and fill us with the deepest emotions (well .. not for you probably). Anyway, the melody in a Sonata plays an almost equal role as harmony in the determination of how to write a sonata.

Now, a melody is no easy thing to come up with, though. What I find effective to think up melodies are long walks, showers, and people that I interact with. Music seemingly springs into my mind, and as a composer, it is my duty to write them down in some form or another. Now, I think that the only REAL reason why I come up with such music in my head is that I've listened to so much music in my life that I just take random parts from random different pieces/songs and just glue them together in my head. The product is usually original, though =P .

<music>{\relative c {\time 4/4 r8 g g g ees2\fermata r8 f f f d2\fermata } } </music>

Theme from Symphony No.5 (Beethoven)

Back to sonata form, a hodgepodge of 289 different melodies won't be in any shape or form a pleasing experience for a listener. You need a melody that unites the overall work and with which listeners can identify. This is what ordinary people refer to as a "catchy tune". For example, most of Beethoven's symphonies have a very catchy melody that is repeated throughout the piece. See Symphony No. 5, Movement 1 or Symphony No. 3, Movement 1 for a good example. That melody at right which almost everyone knows: — is the basis for the entire piece and unites it. A melody that unites an entire piece is called a theme.


As discussed in Part 1, Themes can be likened to characters of a novel. They each have their own background, their own way of acting, and their own unique history. These characteristics are what make unique and original themes so special. The background for themes can be any of these following things: the tonal region they start in, the particular voicings, the orchestration, or the contour. The interactions between themes are the harmonies that come out of the theme interacting with other voices and the texture that is the result of the counterpoint underneath the theme. The history behind the theme is one of the most important things: motifs.

Motifs and Themes are not the same thing. Rather, A theme is something made of many motifs. A motif can be anything the composer chooses. For example, in Beethoven's 5th Symphony's 1st movement, the main theme contains arguably two motifs. The first is the three repeated notes, and the second is the movement by third downward from the G to Eb and F to D. When you put these two motifs together, you get a theme.

Music and novels diverge, though, in one plain and simple fact: music happens instantaneously while reading can be prolonged over a long period of time depending on the reader. By default, grabbing and holding the listener is much much more difficult in music. Therefore, your themes have to stay in your listeners mind. As I said before, a piece with 289 melodies is NOT going to be interesting because the listener will see no development and no movement whatsoever. It should be in the composer's tastes to repeat a theme as needed. If they feel like the listener may have forgotten a theme in a certain point in music, the composer can choose to repeat it (either verbatim or through a slight variation). Since themes are made of motifs, it is important for the motifs to be in their correct sequence and order. Do not depend on many repeats either, though, because that will bore the listener too. A composer should find the perfect balance between repetition and variation.

The specifics of themes

As was mentioned earlier, a theme is something highly personal. I usually get them in the shower or when I'm pondering life's problems. The important part is that you write at least an antecedent. Here's where it might get a little confusing: Although themes can be seen as literary "characters", they can also be seen as literary "thesis statements" like in essays. Thesis statements, like themes, come in a few different forms, but each have their own disadvantages and advantages.

From now on, I will be using the point-of-view of Schoenberg (a composer and scholar of the early 20th century).


The period theme construction is something that has been used since the beginning of the classical era and is based around the simple fact of symmetry although later composers sought to distort it. The period consists of ONLY an antecedent and a consequent. The antecedent can be as short as 2 bars and as long as 12 bars depending on the melody that inspired you. The consequent, though, is usually just as long as the antecedent (in the late-romantic era, this symmetry was often broken, resulting in themes of 7 bars or 9 bars or 11 bars). The most important part of the antecedent, though, is that your original melody must end on a note within the V chord of the tonal region that you are in. The consequent begins on that note and usually finishes off in a deceptive cadence. Although the rhythm and harmony can all be varied from antecedent to consequent, there is usually some constant factor in both sides, whether this be the melodic rhythm or the harmonic rhythm or even the chord progression. Symmetry is essential as well as avoiding the tonic. The I chord is never reached throughout the whole period theme construction besides the beginning.

Periods, due to their symmetric nature, have a way of sticking in people's minds. Therefore, the composer does NOT have to repeat the period very often during the development section. The advantage of using the period IS the symmetry. The disadvantage is the (relative) simplicity.


No, hah, a sentence is not followed by a period. At least, not in music. The sentence and period themes are two different types. The Sentence was a favorite of many composers of the late-classical era and the early-romantic era. This is because it has the potential to be expansively developed. However, the rules of the sentence are slightly more defined. The first part of the sentence is the Antecedent (exactly the same as in the period). This Antecedent can be however long you want it to be (2,3,7, even 12 bars). However, instead of a Consequent following this Antecedent, the Antecedent is repeated. It is repeated, though, on an interval. This can be a 2nd (Beethoven's 5th, movement 1) or a 5th (Beethoven's 1st Piano Sonata, Movement 1) or even a 4th (Beethoven's 10th Piano Sonata, movement 1). It must be repeated exactly in melodic contour, melodic rhythm, and harmonic rhythm. After this repetition, a very special harmonic effect occurs. This is called a prolongation. If your repetition causes the melody to end on a IV chord or vii chord or III chord, that chord is used to begin the next part of the theme. This next part of the theme is called Sequencing. And that's what it is. The composer (you) takes a motif from the Antecedent and repeats it many times on different intervals, so it sticks in the listener's mind. Yes, it should start on the chord that you ended your Second Antecedent on. After this sequencing, there is a Pseudo-Coda, which is basically a HALF cadence. You should end on a chord besides I and not use I in the whole sentence besides the beginning.

Sentences are very conducive to development because of their repetitional nature. I prefer sentences. However, sentences can be asymmetrical and foreign to audiences, along with a tendency to return to tonic.

Important: Most compositions don't have just a period or just a sentence. A lot of them have hybrids and a combination of the two. For example, Beethoven's 1st Piano Sonata has an 8 bar sentence to start it off, but it also has a period in harmonic rhythm because the sentence ended on the dominant chord and the period ended on a subdominant region.

Although these are the main types of themes used in sonatas, there are a few other notable types that I won't go too much into detail with because they are just glorified periods or glorified sentences. One such construction is the small ternary, which is a period in ABA' form. The B is a completely new section with SOME relationship to the previous ones (i.e. melodic rhythm, harmonic rhythm, melodic contour), and the A' section is an ornamentally expanded version of the Antecedent. This theme construction works well in building a fractal (insanely symmetric) nature of works, especially ternary works such as Adagios, Waltzes, Nocturnes, and Minuets. They are used in a few sonatas too... just none that I can name right now.

These themes must work to tie in a work, so that a listener can really identify and enjoy a piece of music. It is in a composer's best interest to find a catchy theme and one that easily gets stuck in his/her head. Unity and Symmetry are coinciding principles that give beauty and purpose to music (especially of the Common Practice Era).

Part III. — Form of the sonata

Alright, now that you know how to write a melody for a sonata and you know the relationships between the regions in a sonata, I think it is time to talk structure. This section will most likely be the shortest because the sonata contains a fairly straightforward structure. This may seem like a disadvantage and a restriction of creativity in the mind of the composer, but really, it serves to solidify information well and produce the necessary drama to get the listener involved. The majority of larger works until the end of the 19th century followed this form, and from the 1950's onward, the majority of larger works use this form too.

Some basic forms besides Sonata form are often used as part of sections within the sonata itself. These are forms are: Ternary form, Binary form, Rondo form, and Arch form. Ternary form is pretty self-explanatory: you have three sections, with the first section being similar to the last section (ABA). That second A does not necessarily mean "go back and repeat the first section verbatim", rather, it means use the same theme and generally the same harmonic regions. More specifically, the sections themselves are based on the themes and harmonic regions associated with these themes. Often, the second section of A will contain more ornamentation on the theme to increase interest. The middle section (B) gains flats and is often slowed down in Marches, Minuets, and Scherzos. This section is called the "Trio". Most music of the 18th and 19th century is in ternary form.

Binary form is like Ternary form except it has only two sections, AB.

Rondo form denotes its sections ABACADA and it can be expanded. This evolved from the "ritornello" of a concerto grosso. There is a main theme with some development within it. Then, a section with another theme in another tonal region comes in, and this alternation occurs until the composer decides to end the rondo.

Pre-Exposition (Introduction)

The exposition serves as the setting-up for conflict in the sonata, as I have told you before. The conflict is accentuated by the modulation to the Dominant/Subdominant region after theme A. Theme A is usually in period or sentence form and some works begin immediately with this theme. However, it is also possible to start the piece off with a completely unrelated section. This "introduction" aspect to the sonata is apparent in numerous works over time, and Franz Schubert's works display this trait most prevalently. Schubert's 9th symphony begins with a completely unrelated horn fanfare in a different tonal region than the statement of Theme A. A small clarification is that the region Theme A is in tends to be the tonal region of the overall work. The introduction can be set up in Ternary form, Binary form, or even a short Rondo form. The important function of the introduction is to build up intensity and anticipation before the arrival of the main theme. However, when including an introduction, it is necessary to highlight Theme A more because it can be lost within the exposition otherwise.


The exposition usually begins with the statement of Theme A in the tonal region of the piece, as I've stated above. Examples of this include all sonatas of the 18th and 19th century. After Theme A, there is usually a period of half-motive development with half-new themes. This allows the exposition to feel concrete while at the same time conducive to new ideas. In some of Beethoven's piano sonatas, he takes textural ideas from the Theme A such as suspensions or appogiaturas and develops them by repeating them over and over again on different chords while still keeping the melodic contour and interval relationship within the chord.

It is important to not have any perfect cadences in this part of the exposition.

During this time with a lack of a clear thematic statement, there is usually a section where modulation starts to occur and a new theme starts which is based somewhat loosely on Theme A. This loose basis allows the material that follows to stand out and be marked well in the listener's mind. This section is called the bridge. In order to come up with a good bridge theme, I advocate going back to Theme A and picking out textural things that you like, such as the chord spacing and/or the contour.

After the modulation, the next theme begins. In my sonatas, I try to use different theme constructions between the two themes so that there is some variety to the piece. If this does not work well for you, then you are allowed to use two sentences or two periods or two small ternaries. Theme B is not in the same tonal region as A and it is usually of a different mood or character in order to bring about the most contrast. There is not usually much motive development of Theme B, and the exposition ends with the first perfect authentic cadence at the end of section B in the exposition.


The development is the most structurally loose section of the Sonata, but it is possible to further section the development into ternary form or binary form or rondo form. The most important part of the development, though, is the need for development. Development will be the topic of the next section and is the most vital part of the sonata. Due to the constantly changing nature of this section, it is advised to avoid perfect authentic cadences as much as possible. This can be done through modulation or false cadences. There is no restriction in the amount of modulation that a composer can do in the development section. Within the development, though, the main themes are usually broken up into their motifs or even fragments of motifs. These fragments are then given weight in the sonata as an attempt to characterize the themes. Often, these fragments will be placed in direct counterpoint or indirect counterpoint. A technique which I find to be especially dramatic is a literal clash of conflicting themes during the climax of the development section. This, in my opinion, shows it to be as a literary form too. It is important for the composer to use cadences and natural harmonic motion to his/her advantage in marking important sections and turning points in the Sonata.

The finality of the development is brought about by the dominant pedal to the tonic region and a perfect authentic cadence back to the home-tonal region.


The recapitulation is a reiteration of the first exposition and should remain that way, so many of the structural aspects are similar. However, the bridge is usually absent in the recapitulation because there is no need for modulation. Some composers, though, favored modulating to the subdominant to begin the recapitulation and leaving the bridge theme in the recapitulation. This inevitably leads to a modulation to the home-tonal region by the time that Theme B begins. The "introduction" section is NOT repeated in the recapitulation. After a straight repetition of the exposition in the home key, the coda begins.


Earlier, I used the example of Schubert's 9th symphony as a good example of an unrelated introduction. In the coda, though, the introduction's motives can be repeated in order to bring closure to the listener. In addition, the coda can contain an entirely new melody to end a piece, like in Mendelssohn's Symphony 1, Movement 4. The ending of the Coda usually has a section of many many Perfect Authentic Cadences, cadencing to the tonal home-region.