Voice Leading

Voice Leading refers to using certain voicings for chords dependent upon the previous and next chord in the progression. In other words, when chord 1 uses this voicing, chord 2 should use that voicing. Up until now we have been concerned simply with diatonic progressions and the harmonic functions of chords to construct or analyze a progression. We've briefly touched upon position and voicing but purposefully avoided any details. Well, the time has come!

Origins and Purpose of Voice Leading

Every era of music has developed its own set of "rules" regarding composition. These simply mirror the preferred customs of the day. Again, there is no bad or good music in fact, only in opinion, which tends to fluctuate from person to person and from era to era. The voice leading described here follows the set of boundaries that emerged from composers during the Renaissance and Common Practice Period. They are mostly derived from the rules of counterpoint.

Counterpoint is a compositional style that is mainly concerned with multiple simultaneous melodies. The melodies must have some concern for the harmony their interaction creates. In fact, simply combining two random melodies, even if their rhythms are synchronized and pitches transposed to the same key, will more than likely result in a song that has a confused, directionless, and dissonant harmony. When done well, however, counterpoint was immensely popular. Thus, those in the musical craft began developing rules and frameworks to compose counterpoint that avoided the bad and exploited the good.

While counterpoint and voice leading are separate topics, classical voice leading rules mirror counterpoint. In counterpoint, each melodic line is considered independent. Voice leading comes from a similar line of thought, taking each note of a chord as an independent voice. As chords change, each voice must rise, fall, or hold pitch. Using rules consistent with counterpoint, the specific note of the chord each voice would move to depends on the current notes and possible selections for the other voices.

The ultimate effect of following these rules is, in my opinion, a smooth transition between chords that maximizes the discernability of the change in harmony, while minimizing noticeable changes in pitch.

Rules

Here are some of the rules I was taught:

• 2 voices should not move in parallel fifths or octaves.
• Contrary motion is preferred over parallel motion.
• Voices should not cross, although they can meet at the same note.
• The P4 and P5 intervals must be approached by contrary motion.
• The leading tone should always resolve up to the tonic if it is part of the next chord.
• Smaller movement is preferable to larger movement.