Lesson 10a - Basic Part-writing Errors

Before we move on to fully analyzing harmonic function, we must define the stylistic rules of the music we will be studying. If you remember from the Unit 6 readings discussing laws, rules, and strategies, rules are the practices that define a style. They are the binding agents that create a genre, but they also must be flexible enough for composers to carve out a unique voice within the style. The next two units of this textbook examine the rules established in earlier contrapuntal styles. Not because this is “superior” to any other style, but because these rules allow us to study how to weave independent voices into a single tonal piece of music. This acts as the foundation for most modern styles and is applicable to all tonal musics–even if the goal of the style is to break these rules.

To study these rules, we will focus on part-writing through simple four-part chorales, so in the context of these discussions:

• A voice is an independent melody, and we often assign these a name based on their range (e.g. soprano, alto, tenor, or bass);
• Voice-leading is the collection of rules and guidelines that govern the relationships within a voice;
• Part-writing refers to a musical combination of voices as well as the rules and guidelines that govern the relationships between voices;
• Voicing refers to the process of assigning each voice to a chord member based on the harmony.

Chorales provide two advantages for teaching harmony when compared to other styles of music:

• Chorales are easier to understand visually, because they have less embellishment than most other styles.
• Chorales can easily incorporate all harmonic “advances” introduced over the last three centuries, therefore giving us a method to study the evolution of tonal harmony.

As we progress through rules of early styles that might seem outdated, do not lose sight of the process that we are creating. If you understand why each decision is made in this style, you will be able to intuit the next leap forward. And as we add complexity, you will eventually be able to apply these principles to any style of tonal music, even those that do not employ the underpinnings of indpendent voices or diatonic harmonic progressions.

Part-writing errors

In the following example, each staff system highlights a different error.

• Compare the “Acceptable” chords to the “Unacceptable” chords to come up with descriptions of the first two basic rules of doubling and spacing.
• Because range is a simple maximum and minimum, I have listed conservative estimates for each voice part.
  • These can vary widely depending on the skill level of the intended performers but will be sufficient for our early exercises in part-writing.

Conclusions

To this point, everything that we have discussed has been based on a two-voice model, but to move into full diatonic harmony, we need to add inner voices and fully support the harmonies. When doing this, there are certain rules that create better voice-leading and part-writing when followed, but as with all stylistic guidelines, please note that these rules are generally strong suggestions rather than hard and fast rules. Good composers bend or break these rules if it better serves their ideas.

Doubling

When voicing triads in four-part harmony, at least one note must be doubled.

1. Doubling the root is usually the ideal choice on root position chords and is almost always a reasonable option, regardless of inversion.
2. Doubling the fifth is generally the second best option for triads, and it is often the best option for second inversion triads.
3. Doubling the third is generally unacceptable, although there are certain cases in which this can be necessary, such as some first inversion chords. As a rule of thumb, do not double the third unless you are voicing a chord and/or inversion in which you’ve already been told that doubling the third is the best option.
4. If you need to omit a voice, the fifth is the only option, because the root and third are required to define the chord. Diminished triads are the only diatonic harmony in which the chordal fifth is a critical chord tone, but even in these situations, the fifth might be the best omission if necessary (albeit unlikely).
5. You can triple the root if necessary, but this voicing lacks the depth of a chord with a fifth and can create a difficult voicing to continue writing afterwards. This is most commonly used as an ending chord of the piece (often after a V7).

Doubling in a seventh chord is similar, but because you have four notes for four voices, there is less freedom.

1. There must always be a root, third, and seventh in the chord, because without any of them, the chord is no longer a functional seventh chord.
2. If necessary, you can omit the fifth.
3. If the fifth is ommitted, the root is the only chord tone that can be doubled. Do not double the third or the seventh.

Spacing

Spacing is straightfoward in this style, but it can be difficult to create consistent rules based on the limited examples above. Your final conclusions should be:

• The bass can be as far from the tenor as needed.
• Between the soprano, alto, and tenor voices, adjacent voices cannot be more than an octave apart. Meaning that the:
  • Tenor and alto cannot have more than an octave between them.
  • Soprano and alto cannot have more than an octave between them.
• Tenor and soprano can have more than an octave between them.
  • When the tenor and soprano are within an octave of each other, we call this a closed voicing.
  • When the tenor and soprano are more than an octave apart, we call this an open voicing.

In general, an acceptable voicing will mimic the overtone series on which our harmony is created. This details of this concept are discussed in Unit 11, but a helpful guideline is to use wider intervals between lower voices and narrower intervals between high voices.

Range

The ranges for each voice in the examples are conservative, but will serve us well in our beginning part-writing. These are highly dependent on the intended performers.

Voice-crossing

There was no easy way to notate this in the examples, but you should avoid crossing your voices unless used to create a desired texture. It is almost never necessary and often creates voice-leading and range issues. As you grow in your part-writing, you may find an occasional reason to cross voices, but do not unnecessarily complicate your first attempts.