Koch on Caesuras, Appoggiaturas and Cadences - HCKoch #5

A caesura can remain structurally fixed even while ornament shifts its audible resolution away from the expected beat.

Koch describes the delaying note with terms such as Vorhalt, Vorschlag, and Wechselnote, but he does not use them consistently. His examples are chiefly appoggiaturas: non-harmonic notes that occupy the caesura note’s accented position and require resolution. Whether written small or as an ordinary note, the ornament displaces the proper note without changing the caesura’s structural location.

The appoggiatura may last throughout the strong part of the measure, forcing the true caesura note onto a weak beat. In 3/4, 3/8, or duple metre, the next phrase may begin without an intervening rest, so notation offers no obvious boundary. The division must then be heard through accent, harmony, melodic direction, and continuation: punctuation becomes an act of musical perception.

Two passages may display almost identical notes and rhythms yet perform different formal tasks. In one of Koch’s examples, repeated subsidiary notes decorate an appoggiatura that delays a caesura; in another, the same surface figure merely enlivens notes inside an incise. Reduction to the principal tones exposes the difference: resemblance in notation does not guarantee identity in phrase structure.

The harmony beneath a resting point tells us whether the music has concluded, paused provisionally, or merely changed direction.

Notes may fill the space between a caesura and the opening of the next phrase, joining two units in an unbroken melodic line. Koch distinguishes this connective decoration from the compounding of phrases. The former simply occupies an otherwise empty interval; the latter suppresses an entire measure, or tactus stichon. Smooth continuity on the surface therefore need not erase the underlying division.

Because an incise is incomplete, its caesura may rest on a dissonant harmony, especially the dominant seventh, whose instability naturally demands continuation. A fermata may suspend metrical motion at such a point, but it cannot make the harmony complete. Time may stop while tonal necessity remains impatient: the unresolved chord still requires a following section in which its dissonance is released.

A caesura over the tonic triad creates an I phrase, or Grundabsatz; one over the dominant creates a V phrase, or Quintabsatz, often called a half cadence when continuation follows. Endings on the fourth degree are rarer and must be judged tonally: an apparent IV may actually be the tonic of a modulation. The bass normally takes the root, though a first inversion may serve voice leading and variety.

Koch’s cadence is not a single chord but a measured melodic action whose proportions can expand, contract, and acquire an afterlife.

The basic cadential melody contains three functional notes. A preparation falls on a strong part of the measure; a cadential note follows on the weak part and moves toward the keynote; the closing tone returns on the strong part and serves as the caesura note. These labels do not necessarily describe a contrapuntal suspension: the preparation may be consonant and prepares motion in a melodic and metrical sense.

This three-note design can change scale without losing its identity. In an expanded cadence, preparation and cadential notes each occupy a whole simple measure, turning a four-measure phrase into five; in a diminished cadence, both are compressed into submetrical units. Subsidiary notes may decorate either stage, especially the longer preparation, while the order and function of the principal notes remain intact.

After the cadence is complete, an overhang may grow into an appendix that reinforces the close through repeated tonic chords or alternations of dominant and tonic. These additions confirm an arrival already achieved; they do not create it. A closing phrase may also contain internal incises, but its final cadence governs the whole. Koch thus shows that ornament can conceal structure without dissolving it.