Etude eleven by Fernando Sor corresponds to Estudio seventeen in the Segovia collection. This is one of the more Romantic, stylistically, of the studies to date. Harmonically we have a rather typical plan beginning in E minor, moving to the relative major (G), back to E minor and then to E major (parallel major) for the final section. Sor again uses double suspensions, appoggiaturas and accented passing tones (some chromatic) frequently throughout the piece creating some beautiful dissonances. We also find multiple uses of the passing diminished seventh chord that we discussed previously but in a jazz context.
There are three key areas in the study (E minor, G major and E major) but very little in the way of non-diatonic harmony other than the passing diminished seventh chords and a few secondary dominants. I expected it to be richer harmonically because of its Romantic quality and was surprised to find the harmony to be quite straightforward.
This is probably a good time to review the passing diminished seventh chord as we can now see how it is applied in the context of this piece. As we discussed previously, two chords that are a whole-step apart may be connected chromatically through the use of a diminished seventh chord placed chromatically between the roots of the two chords. For example in the key of C major the diatonic triads are as follows:
C (I) Dm (ii) Em (iii) F (IV) G (V) Am (vi) Bdim (vii).
We can connect the C major chord to the D minor by inserting a C-sharp diminished seventh chord between them as follows:
C – C#dim7 – Dm
We can also connect the D minor with the E minor with the insertion of a D-sharp diminished seventh chord as follows:
Dm – D#dim7 – Em
This process can continue as long as there is a whole-step between the chord roots with the exception of chord vi (Am) to chord vii (Bdim). Since a diminished triad is not considered a point of resolution or stability, moving into a diminished triad with a leading-tone harmony does not occur because the desired effect of tension and release does not exist.
The first instance of this harmony occurs in measure fourteen in which Sor passes from ii in first inversion to V chromatically using a diminished seventh chord. Yes, I know that ii and V are separated by more than a whole-step. It is the fact that the ii chord is in first inversion implying the root of IV that then passes chromatically to V that is the difference. We talked earlier about how the ii and IV chords are interchangeable due to their intervallic relationship of a third. You can confirm this by substituting the ii chord (Am) with the IV chord (C) and noting how similar they sound. You might also try changing the note A in the upper voice in measure fourteen to a G, which would effectively change the harmony from a ii chord to a IV chord and compare the two versions.
The first true instance of this passing diminished seventh harmony occurs in measure twenty-three in which the V and vi chord are chromatically connected. It is interesting to note that in measures fifty through fifty-two Sor uses both the iv and the ii with the same bass (A) which then moves to A-sharp diminished seventh and then to B major (V). There is one final occurrence in measure sixty-seven in which V and vi are connected chromatically.
This is a beautiful study and I am sure you will enjoy working on it. The analytical and performance versions are included below for your use.