In music theory, the tonality of a piece is its perceived key or mode. Tonality centers around a tonic note and chord, where the piece is most stable, and may be indicated by clues such as a key signature or the function of the piece's chords. For example, in the key of Cmajor, the tonic note is C, and the tonic triad is Cmajor (consisting of notes C, E and G). Similarly, in B Lydian, the tonic note is B, and the tonic triad is Bmajor (consisting of notes B, D# and F#).
Simple folk songs, orchestral pieces, and pop songs often start and end with the tonic note. In such pieces, cadences in which the dominant chord or dominant seventh chord resolves to the tonic chord often play an important role in establishing tonality. Harmony in jazz similarly includes certain tonal characteristics of the European common practice period (colloquially known as "classical music"), although not all. Modernistic music, by contrast, was often atonal.
Etymology The term tonalité originated with Alexandre-Étienne Choron and was borrowed by François-Joseph Fétis in 1840.; ; ; . According to Carl Dahlhaus, however, the term tonalité was only coined by Castil-Blaze in 1821.; . Although Fétis used it as a general term for a system of musical organization and spoke of types de tonalités rather than a single system, today the term is most often used to refer to major–minor tonality, the system of musical organization of the common practice period. Major–minor tonality is also called harmonic tonality (in the title of Carl Dahlhaus, translating the German harmonische Tonalität), diatonic tonality, common practice tonality, functional tonality, or just tonality.
Characteristics and features At least eight distinct senses of the word "tonality" (and corresponding adjective, "tonal"), some mutually exclusive, have been identified.
Systematic organization The word tonality may describe any systematic organization of pitch phenomena in any music at all, including pre-17th century western music as well as much non-western music, such as music based on the slendro and pelog pitch collections of Indonesian gamelan, or employing the modal nuclei of the Arabic maqam or the Indian raga system.
This sense also applies to the tonic/dominant/subdominant harmonic constellations in the theories of Jean-Philippe Rameau as well as the 144 basic transformations of twelve-tone technique. By the middle of the 20th century, it had become "evident that triadic structure does not necessarily generate a tone center, that non-triadic harmonic formations may be made to function as referential elements, and that the assumption of a twelve-tone complex does not preclude the existence of tone centers".
For the composer and theorist George Perle, tonality is not "a matter of 'tone-centeredness', whether based on a 'natural' hierarchy of pitches derived from the overtone series or an 'artificial' pre compositional ordering of the pitch material; nor is it essentially connected to the kinds of pitch structures one finds in traditional diatonic music". This sense (like some of the others) is susceptible to ideological employment, as Schoenberg, did by relying on the idea of a progressive development in musical resources "to compress divergent fin-de-siècle compositional practices into a single historical lineage in which his own music brings one historical era to a close and begins the next." From this point of view, twelve-tone music could be regarded "either as the natural and inevitable culmination of an organic motivic process (Webern) or as a historical Aufhebung (Adorno), the dialectical synthesis of late Romantic motivic practice on the one hand with a musical sublimation of tonality as pure system on the other".
Theoretical arrangement of pitches In another sense, tonality means any rational and self-contained theoretical arrangement of musical pitches, existing prior to any concrete embodiment in music.
For example, "Sainsbury, who had Choron translated into English in 1825, rendered the first occurrence of tonalité as a 'system of modes' before matching it with the neologism 'tonality'. While tonality qua system constitutes a theoretical (and thus imaginative) abstraction from actual music, it is often hypostatized in musicological discourse, converted from a theoretical structure into a musical reality. In this sense, it is understood as a Platonic form or prediscursive musical essence that suffuses music with intelligible sense, which exists before its concrete embodiment in music, and can thus be theorized and discussed apart from actual musical contexts".
Contrast with modal and atonal systems To contrast with "modal" and "atonal", the term tonality is used to imply that tonal music is discontinuous as a form of cultural expression from modal music (before 1600) on the one hand and atonal music (after 1910) on the other.
Pre-modern concept In some literature, tonality is a generic term applied to pre-modern music, referring to the eight modes of the Western church, implying that important historical continuities underlie music before and after the emergence of the common practice period around 1600, with the difference between tonalité ancienne (before 1600) and tonalité moderne (after 1600) being one of emphasis rather than of kind.
Referential tonic In a general way, tonality can refer to a wide variety of musical phenomena (harmonies, cadential formulae, harmonic progressions, melodic gestures, formal categories) as arranged or understood in relation to a referential tonic.
Tonal theories In a slightly different sense to the one above, tonality can also be used to refer to musical phenomena perceived or pre-interpreted in terms of the categories of tonal theories.
This is a psychophysical sense, where for example "listeners tend to hear a given pitch as, for instance, an A above middle C, an augmented 4th above E, the minor 3rd in an F minor triad, a dominant in relation to D, or (where the caret designates a scale degree) in G major rather than a mere acoustical frequency, in this case 440 Hz".
Synonym for "key" The word tonality is sometimes used as a synonym for "key", as in "the C-minor tonality of Beethoven's Fifth Symphony".
In some languages, indeed, the word for "key" and that for "tonality" are the same, e.g. French tonalité.
Other perspectives There is a loose assortment of ideas associated with the term.
"Tonal harmonies must always include the third of the chord".
In major and minor harmonies, the perfect fifth is often implied and understood by the listener even if it is not present. To function as a tonic, a chord must be either a major or a minor triad. Dominant function requires a major-quality triad with a root a perfect fifth above the affiliated tonic and containing the leading tone of the key. This dominant triad must be preceded by a chord progression that establishes the dominant as the penultimate goal of a motion that is completed by moving on to the tonic. In this final dominant-to-tonic progression, the leading tone normally ascends by semitone motion to the tonic scale degree.; ; ; . A dominant seventh chord always consist of a major triad with an added minor seventh above the root. To achieve this in minor keys, the seventh scale degree must be raised to create a major triad on the dominant.; .
David Cope considers key, consonance and dissonance (relaxation and tension, respectively), and hierarchical relationships the three most basic concepts in tonality.
Carl Dahlhaus lists the characteristic schemata of tonal harmony, "typified in the compositional formulas of the 16th and early 17th centuries," as the "complete cadence" I–ii–V–I, I–IV–V–I, I–IV–I–V–I; the circle of fifths progression I–IV–vii°–iii–vi–ii–V–I; and the major–minor parallelism: minor v–i–VII–III equals major iii–vi–V–I; or minor III–VII–i–v equals major I–V–vi–iii. The last of these progressions is characterized by "retrograde" harmonic motion.
Form
Consonance and dissonance
The consonance and dissonance of different intervals plays an important role in establishing the tonality of a piece or section in common practice music and popular music. For example, for a simple folk music song in the key of C Major, almost all of the triadic chords in the song will be Major or minor chords which are stable and consonant (e.g., in the key of C Major, commonly used chords include D minor, F Major, G Major, etc.). The most commonly used dissonant chord in a pop song context is the dominant seventh chord built on the fifth scale degree; in the key of C Major, this would be a G dominant seventh chord, or G7 chord, which contains the pitches G, B, D and F. This dominant seventh chord contains a dissonant tritone interval between the notes B and F. In pop music, the listener will expect this tritone to be resolved to a consonant, stable chord (in this case, typically a C Major cadence (coming to rest point) or a deceptive cadence to an A minor chord).
Tonal musics "The larger portion of the world's folk and art music can be categorized as tonal," as long as the definition is as follows: "Tonal music gives priority to a single tone or tonic. In this kind of music all the constituent tones and resulting tonal relationships are heard and identified relative to their tonic". In this sense, "All harmonic idioms in popular music are tonal, and none is without function". However, "within the continuing hegemony of tonality there is evidence for a relatively separate tradition of genuine folk musics, which do not operate completely or even mainly according to the assumptions or rules of tonality. … throughout the reign of tonality there seem to have existed subterranean folk musical traditions organized on principles different from tonality, and often modal: Celtic songs and blues are obvious examples".
According to Allan Moore, "part of the heritage of rock lies within common-practice tonality" but, because the leading-note / tonic relationship is "axiomatic to the definition of common-practice tonality", and a fundamental feature of rock music's identity is the absence of a diatonic leading tone, the harmonic practices of rock music, "while sharing many features with classical tonality, are nonetheless distinct". Power chords are especially problematic when trying to apply classical functional tonality to certain varieties of popular music. Genres such as heavy metal, new wave, punk rock, and grunge music "took power chords into new arenas, often with a reduced emphasis on tonal function. These genres are often expressed in two partsa bass line doubled in fifths, and a single vocal part. Power chord technique was often allied with modal procedure".
Much jazz is tonal, but "functional tonality in jazz has different properties than that of common-practice classical music. These properties are represented by a unique set of rules dictating the unfolding of harmonic function, voice-leading conventions, and the overall behavior of chord tones and chordal extensions".
History and theory 18th century Jean-Philippe Rameau's Treatise on Harmony (1722) is the earliest effort to explain tonal harmony through a coherent system based on acoustical principles, built upon the functional unit being the triad, with inversions.
19th century