Каденция: завершение музыкальной фразы и ее разрешение.

End of a musical phrase with resolution

In Western musical theory, a cadence is the end of a phrase in which the melody or harmony creates a sense of full or partial resolution, especially in music of the 16th century onwards. A harmonic cadence is a progression of two or more chords that concludes a phrase, section, or piece of music. A rhythmic cadence is a characteristic rhythmic pattern that indicates the end of a phrase. A cadence can be labeled "weak" or "strong" depending on the impression of finality it gives. While cadences are usually classified by specific chord or melodic progressions, the use of such progressions does not necessarily constitute a cadence—there must be a sense of closure, as at the end of a phrase. Harmonic rhythm plays an important part in determining where a cadence occurs. The word "cadence" sometimes slightly shifts its meaning depending on the context; for example, it can be used to refer to the last few notes of a particular phrase, or to just the final chord of that phrase, or to types of chord progressions that are suitable for phrase endings in general. Cadences are strong indicators of the tonic or central pitch of a passage or piece.

Cadences are divided into four main types, according to their harmonic progression: authentic (typically perfect authentic or imperfect authentic), half, plagal, and deceptive. Typically, phrases end on authentic or half cadences, and the terms plagal and deceptive refer to motion that avoids or follows a phrase ending cadence. Each cadence can be described using the Roman numeral system of naming chords.

An authentic cadence is a cadence from the dominant chord (V) to the root chord (I). During the dominant chord, a seventh above the dominant may be added to create a dominant seventh chord (V7); the dominant chord may also be preceded by a cadential chord. The Harvard Concise Dictionary of Music and Musicians says, "This cadence is a microcosm of the tonal system, and is the most direct means of establishing a pitch as tonic. It is virtually obligatory as the final structural cadence of a tonal work." Music theorist William Caplin writes that the perfect authentic cadence "achieves complete harmonic and melodic closure."

An evaded cadence moves from a dominant seventh third inversion chord (V) to a first inversion tonic chord (I). Because the seventh of the dominant chord must fall stepwise to the third of the tonic chord, it forces the cadence to resolve to the less stable first inversion chord. To achieve this, a root position V usually changes to a V right before resolution, thereby "evading" the root position I chord that would usually follow a root position V. (See also inverted cadence below.)

A half cadence (also called an imperfect cadence or semicadence) is any cadence ending on V, whether preceded by II (V of V), ii, vi, IV, or I—or any other chord. Because it sounds incomplete or suspended, the half cadence is considered a weak cadence that calls for continuation. Several types of half cadences are described below.

A Phrygian half cadence is a half cadence iv6–V in minor, so named because the semitonal motion in the bass (sixth degree to fifth degree) resembles the half step heard in the ii–I of the 15th century cadence in the Phrygian mode. Due to its being a survival from modal Renaissance harmony this cadence gives an archaic sound, especially when preceded by v (v–iv6–V). A characteristic gesture in Baroque music, the Phrygian cadence often concluded a slow movement immediately followed by a faster one. With the addition of motion in the upper part down to the sixth degree before rising to the tonic, it becomes the Landini cadence. The plagal half cadence is a weak cadence, ordinarily at the ending of an antecedent phrase, after which a consequent phrase commences. One example of this use is in "Auld Lang Syne". But in one very unusual occurrence – the end of the exposition of the first movement of Brahms' Clarinet Trio, Op. 114—it is used to complete not just a musical phrase but an entire section of a movement.

A plagal cadence is a cadence from IV to I. It is also known as the Amen cadence because of its frequent setting to the text "Amen" in hymns.

A minor plagal cadence, also known as a perfect plagal cadence, uses the minor iv instead of a major IV. With a very similar voice leading to a perfect cadence, the minor plagal cadence is a strong resolution to the tonic.

The Moravian cadence, which can be found in the works of Leoš Janáček and Bohuslav Martinů amongst others, is a form of plagal cadence in which the outer notes of the first chord each move inwards by a tone to the second. (IVadd6 → I6). An early suggestion of the Moravian cadence in classical music occurs in Antonín Dvořák’s New World Symphony.

Image frame|content=|width=350|caption=A deceptive cadence in the second movement of Mozart's Piano Sonata No. 10 most commonly V7–vi (or V7–VI) in major or V7–VI in minor. This is considered a weak cadence because of the "hanging" (suspended) feeling it invokes. At the beginning of the final movement of Gustav Mahler's 9th Symphony, the listener hears a string of many deceptive cadences progressing from V to IV6. One of the most striking uses of this cadence is in the A minor section at the end of the exposition in the first movement of Brahms' Third Symphony. The music progresses to an implied E minor dominant (B7) with a rapid chromatic scale upwards but suddenly sidesteps to C major. The same device is used again in the recapitulation; this time the sidestep is—as one would expect—to F major, the tonic key of the whole Symphony. The interrupted cadence is also frequently used in popular music. For example, the Pink Floyd song "Bring the Boys Back Home" ends with such a cadence (at approximately 0:45–50).

An inverted cadence (also called a medial cadence) inverts the last chord. It may be restricted only to the perfect and imperfect cadence, or only to the perfect cadence, or it may apply to cadences of all types. To distinguish them from this form, the other, more common forms of cadences listed above are known as radical cadences.

A Picardy third (or Picardy cadence) is a harmonic device that originated in Western music in the Renaissance era. It refers to the use of a major chord of the tonic at the end of a musical section that is either modal or in a minor key. The example below shows a picardy third in the final chord, from J. S. Bach's Jesu, meine Freude (Jesus, My Joy), mm. 12–13.

This example from a well known 16th century lamentation shows a cadence that appears to imply the use of an upper leading tone, a debate over which was documented in Rome c. 1540. The final three written notes in the upper voice are printed B–C–D, in which case the customary trill on the second to last note should be played using D and C. However, convention implied that the written C should be played as a C in this context, and a cadential trill of a whole tone on the second to last note would then require a D/E, the upper leading tone of D. Presumably, the debate was over whether to use D–C or D–C for the trill.

Medieval and Renaissance cadences are based upon dyads rather than chords. The first theoretical mention of cadences comes from Guido of Arezzo's description of the occursus in his Micrologus, where he uses the term to mean where the two lines of a two part polyphonic phrase end in a unison.

Image frame|content=|width=300|caption=A clausula vera cadence from Lassus's Beatus homo, mm. 34–35. in contrary motion. Image frame|content=|width=340|caption=A three voice clausula vera from Palestrina's Magnificat Secundi Toni: Deposuit potentes, mm. 27–28. In a melodic half step, listeners of the time perceived no tendency of the lower tone toward the upper, or the upper toward the lower. The second tone was not the 'goal' of the first. Instead, musicians avoided the half step in clausulas because, to their ears, it lacked clarity as an interval. Beginning in the 13th century, cadences begin to require motion in one voice by half step and the other a whole step in contrary motion.

A plagal cadence was found occasionally as an interior cadence, with the lower voice in two part writing moving up a perfect fifth or down a perfect fourth.

A rest in one voice may also be used as a weak interior cadence. (a perfect fifth, a sixth, or a third).

The Corelli cadence, or Corelli clash, named for its association with the violin music of the Corelli school, is a cadence characterized by a major and/or minor second clash between the tonic and the leading tone or the tonic and supertonic. An example is shown below.

Another "clash cadence", the English cadence, is a contrapuntal pattern particular to the authentic or perfect cadence. It features the blue seventh against the dominant chord, which in the key of C would be B and G–B–D. Popular with English composers of the High Renaissance and Restoration periods in the 16th and 17th centuries, the English cadence is described as sounding archaic or old fashioned. It was first given its name in the 20th century. The hallmark of this device is the dissonant augmented octave (compound augmented unison) produced by a false relation between the split seventh scale degree, as shown below in an excerpt from O sacrum convivium by Thomas Tallis. The courtesy accidental on the tenor's G is editorial.

A Landini cadence (also known as a Landini sixth, Landini sixth cadence, or under third cadence) is a cadence that was used extensively in the 14th and early 15th century. It is named after Francesco Landini, a composer who used them profusely. Similar to a clausula vera, it includes an escape tone in the upper voice, which briefly narrows the interval to a perfect fifth before the octave.

The classical and romantic periods of musical history provide many examples of the way the different cadences are used in context.

Mozart’s Romanze from his Piano Concerto No. 20 follows a familiar pattern of a pair of phrases, one ending with a half (imperfect) cadence and the other with an authentic cadence:The presto movement from Beethoven’s String Quartet Op 130 follows the same pattern, but in a minor key:

Cadences in jazz are usually simply called cadences, as in common practice harmony. However, a certain category of cadence is referred to as a turnaround (originally called a "turnback" which is more accurate); this is when a cadence functions as a return to an already existing part of a song form such as AABA. In an AABA form, there are two turnbacks: at the end of the first A (A1) in order to repeat it (A2), and at the end of the B section in order to play the A a third time (A3). (The transition from the second A to the B is not a turnback, because the B section is being heard for the first time.) Half step cadences are common in jazz if not cliché. For example, the ascending diminished seventh chord half step cadence, which—using a secondary diminished seventh chord—creates momentum between two chords a major second apart (with the diminished seventh in between). The descending diminished seventh chord half step cadence is assisted by two common tones.

Cadences often include (and may be emphasized or signalled by) a change in the prevailing rhythmic pattern; in such cases the final note of the cadence usually takes more time (a longer note value, or followed by a rest, or both), and within a piece of music the cadences may also share a rhythmic pattern that is characteristic of the cadences in that piece. This method of ending a phrase with some distinctive rhythmic pattern has been called a "rhythmic cadence"; rhythmic cadences continue to function without harmony or melody, for example at the ends of phrases in music for drums. Some styles of music rely on frequent regular rhythmic cadences as a unifying feature of that style. The example below shows a characteristic rhythmic cadence (i. e. many of the cadences in this piece share this rhythmic pattern) at the end of the first phrase (in particular the last two notes and the following rest, contrasted with the regular pattern set up by all the notes before them) of J. S. Bach's Brandenburg Concerto No. 3 in G major, BMV 1048, mvmt. I, mm. 1–2: