To continue with the theme of harmony in practice we will now examine Etude 2 by Fernando Sor (1778-1839) from Douze Etudes op.6 (Meissonier Edition). This etude corresponds to Estudio three in the Segovia collection of Sor studies. This study is in A major and is mainly composed of simple diatonic harmony. To review, the triads in A major are as follows:
A (I) Bm (ii) C#m (iii) D (IV) E (V) F#m (vi) G#dim (vii)
You will notice that the diminished triads that occur in the piece are analyzed as dominant seventh chords (V) rather than as leading-tone (vii) triads. This is because these diminished triads function as rootless dominant seventh chords in that they resolve to tonic or a secondary tonic. Not all diminished triads function in this way but many times they do. It is simpler to consider chords (V) and (vii) as interchangeable as they are in practice. For example:
E7 (EG#BD) without the root (E) equals G# diminished (G#BD).
Remember from our previous discussions on harmony that many times chords related by thirds are interchangeable. It is common practice to think in terms of only three basic harmonies:
Tonic (I), (vi) and (iii)
Subdominant (IV) and (ii)
Dominant (V) and (vii)
Notice how Sor frequently alternates between the (ii) and the (IV) chords and uses (vi) where we would expect (I) as well as the V/vii exchange. Think of these interchangeable triads as slight variations in color of a fundamental sound. This variation is one reason this simple piece maintains our interest.
As in Etude one, make note of the secondary dominants in measures 2, 6, 7 and 13. Also notice the D minor triad in measure fourteen. This is the first occurrence so far of what is called a “borrowed chord” or a harmony that is taken from the parallel minor key. This particular chord (minor iv) is one of the most common. The D minor triad is considered as borrowed from the parallel minor key of A minor. This is a case of modal mixture where chords from the major and parallel minor keys are combined. You can see that the F natural at the end of measure fourteen is simply a chromatic passing tone between the F# (& of 3) and the E (& of 1, measure fifteen). These things never occur in isolation and are always found in the context of voice-leading which refers to the smooth connection of the voices (usually step-wise if possible) in music. Notice how smoothly the supporting harmony moves in this and all of Sor’s compositions.
A couple of other interesting features to note: The delayed resolution to the dominant (E major) triad at the end of section one, measure eight through the use of a double appoggiatura in which the notes F# and A resolve by step to E and G# respectively. Also the delayed resolution at the final cadence (measure sixteen) in which the G# and the D (tritone) are suspended over from the previous harmony and resolved, as all good tritones should be, by moving in contrary motion to a sixth in this case or the root and third respectively of the tonic triad.
Lastly the E# in measure fourteen can be heard either as a chromatic lower neighbor note to the F# on beat two, measure fourteen or as a chromatic passing tone between the E natural in the previous measure (A7 chord) and the F# in measure fourteen. If heard in the second way it would be analogous to our dominant seven sharp-five (A7#5) chord we know and love in jazz. It is interesting to consider how these dissonances evolved over years of use to become more and more acceptable to the ear and are now a common part of modern harmonic vocabulary.
As before, I have included a performance edition and a clean copy with analysis below.