Voice leading (American) or part-writing (British), is the set of rules regulating the melodic movements of individual parts (voices) in all kinds of polyphonic music, or the application of these rules by the composer, especially in a Western classical music context. The expression "voice leading" is used for any kind of music that can be considered to include several voices, i.e. for instrumental ensembles, solo polyphonic instruments (keyboard instruments, lutes, guitars, harps and the like) or vocal ensembles.
Principles of voice leading in jazz include "the interaction beween chords and lines within harmonic progressions [...], the role of outer-voices counterpoint, the types of melodic motion, the retention of common tones, the treatment of dissonance [...]. At the surface level, jazz voice-leading conventions seem more relaxed than they are in common-practice music." "Good voice leading can take a simple chord sequence and transform it into a masterpiece." "Nowadays, especially in pop music, chords and chord progressions are units that have little to do with the old model. That's not to say that they can't, and that popular music has no voice leading in it, but the largest amount of popular music is simply conceived with chords as blocks of information, and melodies are layered on top of the chords."
Other expressions that may directly or indirectly relate to "voice leading" include:
- "Part leading" mixes the American and British versions of the expression; it is unusual.
- "Voice guiding" is unusual. "Guiding voice" or "Leading voice", on the other hand, refer to a concept in Schenkerian_analysis, namely that one of the voices may lead the whole of the polyphonic complex. See Schenkerian_analysis#Linear_progression for an example from Beethoven's Sonata op. 109.
- "Voice management" appears used mainly to denote the management of one's voice in speech or song.
- "Voice progression" more particularly denotes the progression of one individual voice, either alone or in a polyphonic complex. "Progression" in general is used mainly to denote Chord progressions or root progressions.
- "Conduct of parts" is unusual in English. It may appear in translations from the French, where conduite des voix is the usual translation of "voice leading".
- "Leading tone" is the name of the note that leads to the tonic in tonal music.
The score in the following example reproduces the first four measures of Bach's Preludium in C major (BWV 846a) from the Well Tempered Keyboard, volume 1. (a) presents the original score while (b) and (c) present reductions intended to clarify the harmony and voice leading, respectively.
In (b), the same measures are presented as consisting in four block chords: the first and the fourth ones are the same, a triad of C major (I); the second is a minor 7th chord on D (II), inverted to show C in the bass; the third is a dominant 7th on G (V), inverted to show B in the bass.
In (c), the four measures are presented as formed of five horizontal parts (voices) identified by the direction of the stems, each consisting in only three notes: from top to bottom, (1) E F — E; (2) C D — C; (3) G A G —; (4) E D — E; (5) C — B C. The four chords result from the fact that every voice does not move at the same time. To see this, look at the highest note of each chord - E, F, F, and E - this corresponds to 1), the second highest note of each chord is C, D, D, and C - corresponding to 2) etc.
Voice leading is the rules regulating each part individually and all parts togethr in polyphony or counterpoint. These rules, at first glance, are not different from those of counterpoint and the whole question would not seem to require a separate treatment.[example needed] These rules deal with permitted or forbidden melodic intervals in individual parts, intervals between parts, the direction of the movement of the voices with respect to each other, etc. (See Counterpoint for more details on rules, especially in species counterpoint; see also Contrapuntal motion.)
- All musical technique is derived from two basic ingredients: voice leading and the progression of scale degrees [i.e. of harmonic roots]. Of the two, voice leading is the earlier and the more original element.
- The theory of voice leading is to be presented here as a discipline unified in itself; that is, I shall show how […] it everywhere maintains its inner unity.
Schenker indeed did not present the rules of voice leading merely as contrapuntal rules, but showed how they are inseparable from the rules of harmony and how they form one of the most essential aspects of musical composition.[example needed] (See Schenkerian analysis: voice leading).
Principles and conventions of voice leading include smoothness (avoiding leaps and retaining common tones), avoiding all voices moving in the same direction at once, and avoiding parallel perfect intervals. A concern for easy voice-leading (easy, that is, for singers to read and follow) often leads to a predominance of stepwise motion and may assist or replace diatonic functionality.
One of the main laws of voice leading in counterpoint is that the voices should make as few steps as possible and should as much as possible retain common tones between successive harmonies. This principle is variously known as "rule of the shortest way", as "melodic fluency" or as "parsimony". As will be seen from the quotations below, the "rule of the shortest way" appears to concern the progression from chord to chord in part-writing, while melodic fluency and parsimony may concern individual voices.
The rule of the shortest way, which may have been foreshadowed by Rameau's statement that "one cannot pass from one note to another but by that which is closest", was first formally named and described by Johann August Dürrneberger, who wrote:
- For a regular conjunction of chords in the accompaniment, three main principles are generally considered, namely:
- 1. When a chord contains one or more notes that will be reused in the chords immediately following, then these notes should remain, that is retained in the respective parts.
- 2. The parts which do not remain, follow the law of the shortest way (Gesetze des nächsten Weges), that is that each such part names the note of the following chord closest to itself, if no forbidden succession arises from this.
- 3. If no note at all is present in a chord which can be reused in the chord immediately following, one must apply contrary motion according to the law of the shortest way, that is, if the root progresses upwards, the accompanying parts must move downwards, or inversely, if the root progresses downwards, the other parts move upwards and, in both cases, to the note of the following chord closest to them.
Schenker describes the "rule of melodic fluency" as follows:
- If one wants to avoid the dangers produced by larger intervals [...], the best remedy is simply to interrupt the series of leaps - that is, to prevent a second leap from occurring by continuing with a second or an only slightly larger interval after the first leap; or one may change the direction of the second interval altogether; finally both means can be used in combination.
- Such procedures yield a kind of wave-like melodic line which as a whole represents an animated entity, and which, with its ascending and descending curves, appears balanced in all its individual component parts. This kind of line manifests what is called melodic fluency [Fließender Gesang].
Schenker attributed the rule to Cherubini, but Cherubini had only said that conjunct movement should be preferred. The concept of Fließender Gesang is a common concept of German counterpoint theory. Modern Schenkerians made the concept of "melodic fluency" an important one in their teaching of voice leading.
Melodic fluency plays a determining role in neo-Riemannian theory, which decomposes movements from one chord to another into one or several "parsimonious movements" in the voice leading. The parsimonious melodic movements, however, are read here between pitch classes instead of actual pitches, neglecting octave shifts: this allows for complex voice leading, as in the example hereby.
Inner voices and outer voices
In part-writing for a string section or string orchestra, or string quartet, the second violin and viola parts are called "inner voices", because they are sandwiched between the outer voices (first violin in the high register and the bass/cello in the bass register). The inner voices may tend to move stepwise or repeat common tones. The first violins and the bass/cello play the "outer voices". Outer voices may have more leaps and more motion. The concept of "inner voices" and "outer voices" also applies to writing for choral ensemble, polyphonic instruments (keyboards, guitar, etc), and ensembles of winds, brass, and other instruments.
- Terefenko, Dariusz (2014). Jazz Theory: From Basic to Advanced Study, p.33. Routledge. ISBN 9781135043018.
- Schonbrun, Marc (2011). The Everything Music Theory Book, pp.174, 149. Adams Media. ISBN 9781440511820.
- Heinrich Schenker, Harmony, O. Jonas ed., E. Mann Borghese transl., The University of Chicago Press, 1954 (ISBN 0-226-73734-9), p. 177: "...counterpoint (i.e., rules of voice-leading)."
- Heinrich Schenker, Counterpoint, vol. I, transl. J. Rothgeb and J. Thym, New York, Schirmer, 1987, p. xxv.
- Schenker (1987), p. xxx.
- Miller, Michael (2005). The Complete Idiot's Guide to Music Theory, p.193. Penguin. ISBN 9781592574377.
- Bartlette, Christopher, and Steven G. Laitz (2010). Graduate Review of Tonal Theory. New York: Oxford University Press, pg 47-50. ISBN 978-0-19-537698-2
- Jean-Philippe Rameau, Traité de L'Harmonie Reduite à ses Principes naturels, Paris, 1722, Book 4, pp. 186-7: On ne peut passer d'une Notte à une autre que par celle qui en est la plus voisine. An even earlier version can be found in Charles Masson, Nouveau traité des regles pour la composition de la musique, Paris, Ballard, 1705, p. 47: Quand on jouë sur la Basse pour accompagner, les Parties superieures pratiquent tous les Accords qui peuvent être faits sans quitter la corde où ils se trouvent; ou bien elles doivent prendre ceux qu'on peut faire avec le moindre intervalle, soit en montant soit en descendant.
- Johann August Dürrnberger, Elementar-Lehrbuch der Harmonie- und Generalbass-Lehre, Linz, 1841, p. 53.
- Anton Bruckner, Vorlesungen über Harmonielehre und Kontrapunkt an der Universität Wien, E. Schwanzara ed., Vienna, 1950, p. 129. See Robert W. Wason, Viennese Harmonic Theory from Albrechtsberger to Schenker and Schoenberg, Ann Arbor, London, UMI Research Press, 1985, p. 70. ISBN 0-8357-1586-8
- Schoenberg, Arnold, Theory of Harmony, trans. Roy E. Carter. Belmont Music Publishers, 1983, 1978 (original quote 1911). Page 39. ISBN 0-520-04944-6. Schoenberg writes: "Thus, the voices will follow (as I once heard Bruckner say) the law of the shortest way".
- Heinrich Schenker, Kontrapunkt, vol. I, 1910, p. 133; Counterpoint, J. Rothgeb and J. Thym transl., New York, Schirmer, 1987, p. 94.
- Luigi Cherubini, Cours de Contrepoint et de Fugue, bilingual ed. French/German, Leipzig and Paris, ca 1835, p. 7. Franz Stoepel, the German translator, used the expression Fließender Gesang to translate mouvement conjoint. See Schenkerian analysis.
- See for instance Johann Philipp Kirnberger, Die Kunst des reinen Satzes in der Musik, vol. II, Berlin, Königsberg, 1776, p. 82.
- Allen Cadwallader and David Gagné, Analysis of Tonal Music, 3d ed., Oxford University Press, 2011, p. 17.
- Richard Cohn, "Neo-Riemannian Operations, Parsimonious Trichords, and their 'Tonnetz' Representations", note 4, writes that the term "parsimony" is used in this context in Ottokar Hostinský, Die Lehre von den musikalischen Klangen, Prag, H. Dominicus, 1879, p. 106. Cohn considers the principe of parsimony to be the same thing as the "law of the shortest way", but this is only partly true.
- McAdams, S. and Bregman, A. (1979). "Hearing musical streams", in Computer Music Journal 3(4): 26–44 and in Roads, C. and Strawn, J., eds. (1985). Foundations of Computer Music, p. 658–98. Cambridge, Massachusetts: MIT Press.
- "Voice Leading Overview", Harmony.org.uk.