A plagal closure or plagal closure (from the middle of the plague, plague, plague, "lateral, derived" as opposed to authentic) is the chord connection subdominant - tonic which serves as a complete closure
A piece of music composed in the Major Minor Tonality usually ends on the tonic (the chord built on the root note). If the preceding chord is a fourth step in the sense of the step theory or a subdominant in the sense of the functional theory, then this is called a plagal closure. In other words, a plague closure occurs when the final chord is not reached by a fifth, but by a fifth or fourth.
If, on the other hand, the preceding chord is the dominant one, it is an authentic conclusion. The authentic conclusion, as the name implies, is the more common and frequent variant of the concluding form. The plagal closure, on the other hand, is perceived as less stressful, since the basic tone of the fundamental sound type does not occur in the subdominant chord.
Because of its frequent use in sacred music, especially for the acclamation "Amen", the plague close in musical language is also called a church closing. It is often added as a "solemn" addition after the actual ending of a play. In the case of compositions in minor styles, such a plagal closure often leads to major. The minor subdominant in the plagal joint acts "more dominantly" by the minor third, which falls by one semitone into the fifth of the tonic
Also possible is a plagal close above an organ point: the fundamental tone remains in the bass while the subdominant is reached in the form of a sixteenth chord. Because of its relatively weak concluding effect, this variant is to be found particularly in the case of internals within a work.
The plague closure is mainly found in baroque music and can be found singly also in the 19th century, e.g. with Robert Schumann and Johannes Brahms. Edit source text Single-level Edit source text
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