The Sonata-Type Tree


How to use the Sonata-Type Tree

The Sonata Type-Tree is currently an embedded PowerPoint file. To use it, click the ‘full screen’ option at the bottom right corner of the image. Rather than moving between slides in chronological order, please use the page links, home, and back buttons in the grey column to the left of the Sonata-Type Tree to compare the theoretical pathways through the different sonata types. A short explanation of the colour-coded symbols and acronyms can be found on the ‘Key’ page.

Please note that the diagram may not be compatible with some blog or RRS readers and you may have to visit this website to view it.

About the Diagram

Using this tool requires a knowledge of Sonata Theory that surpasses a familiarity of terminology and acronyms to require an understanding of the formal musical features that define the repertory of late eighteenth-century sonata movements. These include, but are in no means exclusive to, the first and last movements of solo sonatas, string quartets or other chamber genres, and symphonies. A brief guide to the types can be found below but this should be supplemented with James Hepokoski’s and Warren Darcy’s chapters on the types in their Elements of Sonata Theory: Norms, Types, and Deformations in the Late Eighteenth-Century Sonata.

The tree diagram represents musical time vertically from top to bottom, with the pathways through each sonata type branching off to the left or right. For the sake of consistency, space is not used to signify tonal distance in the way that Hepokoski and Darcy’s well-known figure does (Fig. 2.1, p. 17) or Seth Monahan’s adapted version in Mahler’s Symphonic Sonatas (Fig. 1.1, p. 1). These two figures stagger non-tonic theme areas (S or C) on a higher horizontal plane to those in the tonic (P), whereas my diagram uses black to represent tonic material, white to represent non-tonic material and grey to represent material with a tonicizing function (TR/RT). A small gap has been left between TR and S to represent the medial caesura.

A Brief Guide to Sonata Types

TYPE 1 (expanded)

A bi-rotational sonata type lacking repeat marks.

After a retransition, the second rotation (R2) begins with a tonic statement of the primary theme (P), followed by an interpolated developmental ‘expansion’. After this diversion, the rotation begins to correspond to the exposition’s material again, most notably with the secondary theme area (S) in the tonic, thereby rendering the entire section a recapitulation. A coda, likely based on primary material may follow.


Another bi-rotational sonata type.

The opening of the second rotation (R2) is something of an unknown in this type, but it is often developmental and might involve P and/or TR material. At some point in this section, the music begins to correspond to the exposition’s materials in the tonic at some point, at least by the end of the secondary theme area. A coda, likely based on primary material may follow. Due to the lack of ‘double return’ in this form (P + tonic) before the ESC, this type is not considered to have a recapitulation at all. This type is defined in opposition to theories that do not require a rotational ordering of materials within a section: ‘reversed recapitulations’ or ‘mirror’ forms. The most common of these theoretical layouts is also shown on the Sonata Type Tree Diagram.


The traditional ‘textbook’ sonata type.

After a development, a full recapitulation follows, in which all of the expositions materials appear in order, transposed into the tonic. A coda may follow.


A sonata-rondo hybrid type.

Rather than existing as an entirely separate form to the Type 3 sonata, Hepokoski and Darcy theorise that Type 4 sonatas lie somewhere on a continuum between a Type 3 and a symmetrical seven-part rondo. The primary and secondary themes of a Type 4 correspond neatly to rondo-refrains and episodes. The transition (TR) between these theme areas gives this form some of its sonata status. Every section or rotation of this form begins with the primary theme-refrain, or at least part of it, in the tonic, including in the development. The recapitulation is followed by a P-refrain based coda.

Why not Type 5?

Though the Type 5 sonata (a ritornelli-concerto hybrid form) is related to the other types, it is complicated enough to exclude from the Sonata Type Tree, for now at least.

Read more about the Sonata-Type Tree here.