CADENZA in its simplest acceptation is a flourish of indefinite form, introduced upon a bass note immediately preceding a close of some finality; that is, occupying the position of full stop either to an entire movement, or to an important section of one. The custom was most probably originated by singers, who seized the opportunity afforded by the chord of 6–4 on the dominant immediately preceding the final close of an aria or scena, to show off the flexibility, compass, and expressive powers of their voices to the highest advantage; so that the piece coming to an end immediately afterwards, the audience might have the impression of astonishment fresh in their minds to urge them to applause.

The idea thus originated spread widely to all kinds of music, and in course of time its character has changed considerably, though the flourish of which it is composed is still its conspicuous feature. In instrumental music it fulfils a peculiar office, as it is frequently introduced where a pause in the more important matter of the movement is desirable, without breaking off or allowing the minds of the audience to wander. Thus it occurs at points where the enthusiasm of the movement has been worked to such a heat that it is necessary to pause a little before returning to the level of the natural ideas of the themes, as in Liszt's 'Rhapsodie Hongroise' in A, and Chopin's 'Notturnos' in F minor and C♯ minor. Chopin uses them frequently when the main business of the movement is over, in order to prevent the close, which follows immediately, being too abrupt. At other times it occurs as a connecting link between two movements, or between an introduction and the movement following it, where for certain reasons it is expedient to pause a while on some preparatory chord, and not to commence serious operations before the minds of the audience have settled to the proper level.

Specimens of this kind are common in the works of many great masters—e.g. Beethoven's Sonata in E♭ (op. 27, No. i), Adagio; Sonata pathetique; Variations in F (op. 34); Brahms's Sonata in F♯ [App. p.574 amends to F♯ minor] (op. 2, last movement); Mendelssohn's 'Lobgesang,' connecting the first movement with the second.

The greater cadenza, which is a development of the vocal flourish at the end of a vocal piece already spoken of, is that which it is customary to insert at the end of a movement of a concerto for a solo instrument. Like its vocal predecessors the cadenza usually starts from a pause on a chord of 6–4 on the dominant, preparatory to the final close of the movement, and its object is to show off the skill of the performer. Such cadenzas may occur either in the first or last movement, and even in both, as in Mozart's Concerto in D minor and in Beethoven's in G. With regard to their form there is absolutely no rule at all. They should contain manifold allusions to the chief themes of the movement, and to be successful should be either brilliant or very ingenious; containing variety of modulation, but rather avoiding progressions which have been predominant in the movement itself; and the more they have the character of abandonment to impulse the better they are. It was formerly customary to leave the cadenzas for improvisation, and certainly if the frenzy of inspiration could be trusted to come at the right moment, impromptu cadenzas would undoubtedly be most effective in the hands of real masters of the situation. Moreover, it is chiefly in the sense of their being the exposition of the player's special capacities that they are defensible, for as far as the composer is concerned the movement generally offers full opportunities for display of the powers of the executant.

Still custom is generally stronger than reason, and it does not seem likely that cadenzas will yet die out. And as the art of improvisation is for various reasons considerably on the wane it will probably become habitual for composers to write their own cadenzas in full, as Beethoven has done in the E♭ Concerto, and Schumann in his A minor Concerto.

Beethoven also wrote cadenzas for his other concertos and for Mozart's D minor; and these are published separately. Many famous musicians have supplied the like for classical concertos, Moscheles for Beethoven's, and Hummel for Mozart's.

The indication for a cadenza, when not written out in full, is a pause or fermata
{ \override Score.TimeSignature #'stencil = ##f \new RhythmicStaff \stopStaff s\fermata }
indicating its comencement, usually over a rest in the solo part, and

over the last note in each of the orchestral parts; another pause over a shake in the solo part indicating its close. The example is taken from Beethoven's Concerto in C minor, pianoforte part.

{ \override Score.TimeSignature #'stencil = ##f \override Score.Clef #'stencil = ##f << \relative d'' { r2\fermata \afterGrace d2\trill\fermata { c16[ d] } }
\new Staff { \clef bass r2\fermata <g b! f'>\fermata } >> }