Section 23.2 The V7 and Ger+6 as Pivot Chords
In this first type of enharmonic modulation, the pivot to the new key will consist of the \(\left.\text{V}^{7}\right.\) being enharmonically reinterpreted as a \(\left.\text{Ger}^{+6}\right.\), or the \(\left.\text{Ger}^{+6}\right.\) being enharmonically reinterpreted as \(\left.\text{V}^{7}\right.\). Secondary dominants, like \(\left.\text{V}^{7}\middle/\text{IV}\right.\), \(\left.\text{V}^{7}\middle/\text{V}\right.\), etc., will also be reinterpreted harmonically as \(\left.\text{Ger}^{+6}\right.\) chords (and vice versa) in enharmonic modulations.
As we saw in the previous section, the dominant seventh chord and the \(\left.\text{Ger}^{+6}\right.\) chord have the same sound but are spelled differently. This involves a fairly straightforward enharmonic respelling. Most commonly, the top note of the chord is enharmonically respelled to envision the enharmonic alternative.
Each chord above implies a key based on its spelling: the dominant seventh chord occurs diatonically only on the \(\hat{5} \) scale degree in major, while the \(\left.\text{Ger}^{+6}\right.\) chord most commonly occurs with the lowest note on the lowered \(\hat{6} \) scale degree.
Less commonly, the bottom three notes could be respelled and the uppermost note could be retained as a common tone.
Remember, you will not see this respelling in the music you are analyzing. You must be able to visualize the enharmonic respelling in order to analyze the enharmonic modulation correctly.
The examples below illustrate some of the ways this enharmonic modulation occurs in pieces from the literature
In the first example from Tchaikovsky’s Nutcracker ballet, a \(\left.\text{D}^{7}\right.\) is spelled on the staff as D–F♯–A–B♯ so that it sounds like a \(\left.\text{V}^{7}\middle/\text{IV}\right.\) in D major but is spelled and resolves as a \(\left.\text{Ger}^{+6}\right.\) in the key of F♯ minor.
In the following example from the second movement of Beethoven’s Fifth Symphony, the same pivot chords are used as in the example above—\(\left.\text{V}^{7}\middle/\text{IV}\right.\) in A♭ major is enharmonically respelled and resolves as a \(\left.\text{Ger}^{+6}\right.\) in C major.
In the following example from Les Miserables, a \(\left.\text{Ger}^{+6}\right.\) in E minor is spelled as a \(\left.\text{V}^{7}\right.\) chord in F major and resolves to the I chord F major.
In the next section we will examine how the fully diminished seventh chord can be enharmonically reinterpreted.
