SOUND PATTERNS

A Structural Examination of Tonality, Vocabulary, Texture,
Sonorities, and Time Organization in Western Art Music

by PHILLIP MAGNUSON

CHROMATIC PROCEDURES I

Chapter 21. Modulations

Chapter 20. Tonicizations
.
Chapter 22. Hybrid Areas

21.1 DEFINING MODULATIONS

MODULATIONS are similar to tonicizations, but go one step further: they actually leave the global key. As stated in Chapter 14, key is defined by cadence, so a modulation must have a cadence in the new key to confirm the change.

The keys most likely to be used in modulations are CLOSELY RELATED keys, which are those keys that contain key signatures within one accidental of the global key. The closely related keys to C major (no sharps or flats):

D minor (one flat)
E minor (one sharp)
F major (one flat)
G major (one sharp)
A minor (no sharps or flats)

These keys are directly related to the five harmonic areas which can be tonicized:

D minor supertonic key
E minor mediant key
F major subdominant key
G major dominant key
A minor submediant key

When a modulation takes place it is necessary to identify the new key. The new key will be presented in terms of its relationship to the global key, and be expressed as a Roman numeral:

D minor supertonic key ii
E minor mediant key iii
F major subdominant key IV
G major dominant key V
A minor submediant key vi

Closely related keys to a minor global key follow a similar pattern, but there are some important differences. The five closely related keys to C minor (three flats) are

Bb major (two flats) subtonic key VII
Ab major (four flats) submediant key VI
G minor (two flats) minor dominant key v
F minor (four flats) subdominant key iv
Eb major (three flats) mediant key iii

Keys with more than one accidental difference are DISTANT keys, and will be discussed in Chapter 37.

21.2 COMMON CHORD MODULATIONS

Modulations should be considered important and somewhat extended events. A tonicization is usually brief but a modulation is a commitment to a new key area. Consequently, a modulation needs some important basic information to indicate that it has happened. The most frequent modulation is the COMMON CHORD modulation, which indicates that there is a chord in common to both the old key and the new key. The common chord acts as a pivot.

Common chord modulations must show three things:

  1. The new chord, which usuallly contains a chromatic pitch and cannot be identified in the global key.
  2. The new key, which is expressed as a Roman numeral and shows its relationship to the global key.
  3. The common chord, which immediately precedes the new chord and indicates its function in both the old and new key. Brackets are placed around the pair of Roman numerals.

    Learn more about common chord modulations

Once a modulation from the global key to a new key has taken place, it is inevitable that it will eventually modulate back to the global key. The process defined above also applies to this motion back.

21.3 CHROMATIC MODULATIONS

Another way to change keys is a CHROMATIC modulation. A common chord modulation relies on some similarity between two keys (the common chord); a chromatic modulation relies on the difference between two keys (chromatic pitches). Chromatic modulations are significantly more rare than the common chord variety, and should only be used when there is clear chromatic motion, usually found in the same voice.

Chromatic modulations must show three things:

  1. The new chord, which usuallly contains a chromatic pitch and cannot be identified in the global key.
  2. The new key, which is expressed as a Roman numeral and shows its relationship to the global key.
  3. A dividing line between the last chord in the old key and the new chord.

Notice the A to A# motion in the soprano; beat 4 is in E major, beat 1 of the next measure is in B major, the dominant key.

21.4 FORMAL MODULATIONS

On occasion, a modulation occurs at the beginning of a new phrase, or at the beginning of a new section. These are known as FORMAL modulations; they can also be called PHRASE, DIRECT, or ABRUPT modulations.

Formal modulations must show two things:

  1. The new chord, which usuallly contains a chromatic pitch and cannot be identified in the global key.
  2. The new key, which is expressed as a Roman numeral and shows its relationship to the global key. This will be placed at the beginning of the new phrase.

21.5 STRUCTURAL ANALYSIS OF MODULATIONS

As with tonicizations, modulations do not significantly affect structural analysis. Since structure defines general functions rather than specific pitches, it does not matter if an authentic cadence is in the global key or the new key.

The examples below show the structural analysis of the three modulations above.

ASSIGNMENTS:

ANALYSIS

Describe the phrase design and provide a Roman numeral and structural analysis for the following pieces in Music for Analysis:

  1. Mozart: Symphony No. 39, K.543, III [#206] Listen to a performance
  2. Mozart: Sonata, K.331 [#207, CD track #37]
  3. Beethoven: Symphony No. 2, op.36 [#208] Listen to a performance
  4. Chopin: Mazurka, op.7, no.2 [#213, CD track #40]
  5. Haydn: Sonata in E Minor, Hob. XVI: 34 [#218, CD track #43]

SYNTHESIS

Add soprano, alto, and tenor lines to this figured bass, and include, using the indicated rhythm, multiple passing tones, neighbor tones, and suspensions (never more than one in any given beat) in the upper three voices. Circle and label the non-chord tones and provide a Roman numeral and structural analysis:

To prepare this writing assignment properly, use the notation guidelines appendix, located at Basic Principles of Music Notation, Semester II.


Links to chapters in this unit:
Chapter 20. Tonicizations
Chapter 22. Hybrid Areas

Link to previous unit: DIATONIC PROCEDURES III: Substitutions

Link to next unit: THE ABC's OF CHORALE SETTING


Copyright 2008-2009 by Phillip Magnuson.

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