Chapter 15ModulationModulationModulation is the process that
results in the shift of the tonal center. In other words, a key
change.Most modulations occur between closely related keys. A
closely related key is a key that differs by no more than one
accidental in the key signatureAn easy way to understand modulation
is observe the ebb and flow of circle progressions.Modulation3
Types that we will focus on:Common ChordChromaticPhrase
Common ChordBoth keys have a chord that is common in each
respective keyThis offers a smooth transition to the new key
because the chord is diatonic in both keysAlso called a pivot chord
because it is a middle ground between two keysCalled a Common Chord
ModulationChromaticOccurs at the point of a chromatic
progressionThe letter name remains the same but has an
accidentalOccurs when the two keys are not closely relatedDOES NOT
HAVE A COMMON CHORD!Called a chromatic modulationPhraseAlso known
as a direct modulationOccurs between phrases, periods, or larger
sections where a phrase cadences in one key, and the next phrase
begins in the new keyAnalytical SymbolsUse the following symbols to
analyze modulations:Common chord modulations select the common
chord and analyze it in both keys:C: I ii6 V I vi6 G: ii6 V IOther
types of modulation name the new key and adjust chord analysis
accordingly:G: I V I a: V6 i V iHow to spot a modulationPlay the
music you are analyzing. This can sometimes be sufficient to
recognize a modulation.Look for accidentals that are not part of
the established key.Look for a cadence in the new key. Look for
V-I, I-V, IV-V.If you have enough evidence to support a modulation,
look back to the first accidental and determine whether the chord
before it can be analyzed in both keys. If so, you have a common
chord modulationIf the nondiatonic (the accidental) note is taken
chromatically, then you have a chromatic modulation.Secondary
Dominant vs. ModulationSecondary dominants have one accidental
(nondiatonic note) in only one chord.Will usually resolve to its
temporary tonic.Carefully observe the progression.If the
progression seems odd, then a modulation has probably taken
place.Not all modulations will have an accidental. Macro
AnalysisAnalyze and entire section with the macro analysis letter
symbols. Do this before considering key centers or Roman
numerals.After completing the macro, go back and read through the
analysis. Pay attention to symbols that change from the established
pattern at the beginning.Macro AnalysisAfter different symbols are
identified, scan the area containing the new symbol to determine
where the modulation beings and ends. Study the score both before
and after the symbol change.Complete the macro with circle
progression slurs.When the macro analysis is completed, add key
indications and Roman numerals.
