Voice leading

Voice leading (or part writing) is the linear progression of individual melodic lines (voices or parts) and their interaction with one another to create harmonies, typically in accordance with the principles of common-practice harmony and counterpoint.All musical technique is derived from two basic ingredients: voice leading and the progression of scale degrees . Of the two, voice leading is the earlier and the more original element.This rule was taught by Bruckner to Schoenberg and Schenker, who both had followed his classes in Vienna. Schenker re-conceived the principle as the 'rule of melodic fluency':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 . Voice leading (or part writing) is the linear progression of individual melodic lines (voices or parts) and their interaction with one another to create harmonies, typically in accordance with the principles of common-practice harmony and counterpoint. Rigorous concern for voice leading is of greatest importance in common-practice music, although jazz and pop music also demonstrate attention to voice leading to varying degrees. In Jazz Theory, Dariusz Terefenko writes that 't the surface level, jazz voice-leading conventions seem more relaxed than they are in common-practice music.' Marc Schonbrun also states that while it is untrue that 'popular music has no voice leading in it, the largest amount of popular music is simply conceived with chords as blocks of information, and melodies are layered on top of the chords.' The score below shows the first four measures of the C-major prelude from J.S. Bach's The Well-Tempered Clavier, Book 1. Letter (a) presents the original score while (b) and (c) present reductions (simplified versions) intended to clarify the harmony and implied voice leading, respectively. In (b), the same measures are presented as four block chords (with two inverted): I - II42 - V65 - I. In (c), the four measures are presented as five horizontal voices identified by the direction of the stems (which are added even though the notes are actually whole notes). Notice that each voice consists of just 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 the voices do not move at the same time. Voice leading developed as an independent concept when Heinrich Schenker stressed its importance in 'free counterpoint', as opposed to strict counterpoint. He wrote: 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. (See Schenkerian analysis: voice leading.) Western musicians have tended to teach voice leading by focusing on connecting adjacent harmonies because that skill is foundational to meeting larger, structural objectives.Common-practice conventions dictate that melodic lines should be smooth and independent. To be smooth, they should be primarily conjunct (stepwise), avoid leaps that are difficult to sing, approach and follow leaps with movement in the opposite direction, and correctly handle tendency tones (primarily, the leading-tone, but also the , which often moves down to ). To be independent, they should avoid parallel fifths and octaves. Contrapuntal conventions likewise consider 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. Whether dealing with counterpoint or harmony, these conventions emerge not only from a desire to create easy-to-sing parts but also from the constraints of tonal materials and from the objectives behind writing certain textures.