Download Tonal Harmony Chapter 23 Enharmonic Spellings and Enharmonic

Chapter Twenty-Three
Enharmonic Spellings and Enharmonic Modulations
Enharmonic Spellings
 Rationale for enharmonic spellings:
1. To indicate clearly the direction in which a pitch will move
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vii07 changes from a bo7 to a g#o7, but it does not change its sound or its function
or the analysis
when the viio7 moves directly to V, the Ab spelling poses no problem
2. The desire on the part of the composer to make things easier for the performer (e.g. Fb,
the bVI of Ab) (Schubert’s String Trio, there is a modulation from Bb to Gb (bVI), which
then changes by mode mixture into gb minor…….WAIT a minute 9 flats!!!!!, Schubert
quite reasonably notates it in f# minor)
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Enharmonic spelling for convenience is NOT the same as enharmonic modulation
Enharmonic Reinterpretation
 So far, all enharmonic discussed so far is intended primarily for the eye, not the ear
 There are FOUR sonorities used in tonal music can be reinterpreted enharmonically in a different
key ( NOT in enharmonic keys, like Gb and F#)
1. Major-minor seventh: can be serve either as a V7 OR as a Ger+6
2. Diminished seventh chord: any tone can serve as the leading tone
3. Augmented triad (less commonly used for enharmonic reinterpretation)
4. Fr+6 chord (less commonly used for enharmonic reinterpretation)
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This process, which is often reserved for especially dramatic spots in a composition, is known as
enharmonic modulation
Enharmonic Modulations Using the Major-Minor Seventh Sonority
 The term enharmonic modulation is used to refer to a modulation in which the common chord
is reinterpreted enharmonically to fit into the second key
 The common chord might spelled as it would appear in the first key, or in the second key, or even
in both if it occurs more than once
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The V7/IV in G can resolve to IV in G OR treated as Ger+6 in C and resolve to a I 64 in B
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Noticed that the analysis of the first chord in m41 is not a common chord (G:I = BbVI). This is
because it is the cadential six-four chord in m.42 not the V7/IV = Ger+6, that tells us that a
modulation is taking place. REMEMBER to always look for the common chord by backing up
one chord from the chord that signals the modulation
Any V7 chord or secondary V7 in the first key can be reinterpreted as a Ger+6 chord in the new key
The reverse is also possible
In the majority of cases, the common chord is a Ger+6 in the second key, because it has a more
dramatic effect
The major-minor seventh chord in the first key seems most often to be a V7/IV
It would also be possible to use an It+6 as the enharmonic equivalent of an incomplete V7 (not
often because of doubling problems)
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Enharmonic Modulation Using the Diminished Seventh Chord
 The diminished seventh chord is not used as frequently as the major-minor seventh chord in
enharmonic modulations (SURPRISINGLY)
 Diminished seventh chord can lead in FOUR directions, while the major-minor seventh leads
only to two
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Top staff of Example 23-8 shows four resolutions of the same diminished seventh sonority
Bottom staff is similar, except that the diminished seventh chord in each case is followed by a V7
before the resolution to tonic
Both methods viio7 – I and viio7 – V – I are used in enharmonic modulations
Other Examples of Enharmonicism
 Major-minor seventh chords and diminished seventh chords are sometimes used enharmonically
at a more local level