Etude three by Fernando Sor corresponds to Estudio eleven in Segovia’s collection of Sor studies. This is the first piece up until now to use two keys; E major and E minor. This key relationship is known as a parallel relationship and is found quite often in music and is one of my personal favorites. It is also a perfect example of a piece that lets us compare the harmony in major and minor keys. Let’s first review and compare the triads in E major and E minor:
E major: E (I) F#m (ii) G#m (iii) A (IV) B (V) C#m (vi) D#dim (vii)
E minor: Em (i) F#dim (ii) G (III) Am (iv) B (V- harmonic minor) C (VI) D#dim (#vii-harmonic minor)
I have shown the most commonly used chords when in a minor key. In most cases they are derived from a combination of chords from natural (pure) minor and harmonic minor.
The change of key is easily seen in this piece because Sor actually changed the key signature. It is cleaner to do it this way rather than writing all sorts of accidentals. I have shown the key centers in the traditional way with a capital letter followed by a colon for major keys and a lower case letter followed by a colon to indicate minor keys.
There are two important harmonic features to note in this piece; the first is the use of secondary leading-tone chords and the other is the use of what is called a Neapolitan Sixth chord.
Secondary leading-tone chords are used exactly like secondary dominants in that they temporarily “tonicize” another chord in the key. Remember that the diminished triad and diminished seventh chords occur on the seventh degree (leading-tone) of the major scale and the raised seventh degree (leading-tone) of a minor scale (harmonic minor). They usually resolve up by half-step to the tonic chord. There is an important distinction to be made between the quality of the seventh when included in a major and a minor key. When in major the seventh chord built on scale degree seven is a half-diminished seventh chord where as in minor the seventh chord built on the raised seventh degree of the scale is a full-diminished seventh chord. The difference is in the quality of the seventh. In a half-diminished seventh chord the quality of the seventh is minor and in a full-diminished seventh the quality of the seventh is diminished. For example:
C half-diminished7 = C Eb Gb Bb
C full-diminished7 = C Eb Gb Bbb
In jazz we call the half-diminished seventh chord a minor7b5 which to me is a clearer way of indicating this type of seventh chord.
Both types are used in this piece. In measure three we find the half-diminished seventh chord built on the raised fourth degree (I am including the G# in the upper voice, beat four, in my spelling). We also find the full diminished seventh chord in measure eleven built on the raised fourth degree of E minor. Both function as secondary leading-tone chords resolving to the dominant (V) chord B major.
The Neapolitan Sixth chord occurs in measure nineteen, beat three. This chord type is a major triad built on the flatted second degree of the scale and usually is in first inversion, which is what the sixth refers to. In this piece it is an F major triad (lowered second degree in E major/minor) with an A in the bass (first inversion). It usually moves to the dominant, as it does in this piece in measure twenty, although it first passes chromatically through another secondary leading-tone chord. You might notice that the chord on beat one of measure twenty is an E minor triad yet I have labeled it as (V). Tonic triads in second inversion (fifth in the bass) are considered as dominants with a double suspension in which the sixth and fourth above the bass (G and E) resolve to the fifth and third (F# and D#) respectively.
Also notice the move into the relative major (G) and the subdominant (A minor) in the E minor section.
Below are the performance and analytical versions of Etude 3. My hope is that in reading through these studies with the harmonic analysis you will better understand the harmonic concepts we have been studying. I have always believed the best learning is achieved through doing. Enjoy!