Technique in Focus: “On the use of (sequences of) 6/5s”

Regola 34 by Durante focuses on the Down 3rd, Up 2nd sequence (this schema is also an example of an inverted Cycle of Fifths). I have used the term ‘Fonte’ to apply to this sequence rather than just the Fonte as prescribed by Riepel (Gjerdingen, 2010, p. 66). The Italin word fonte translates to ‘fountain’, or ‘well’ and indicates a bass descent of a 3rd followed by the ascent of a 2nd. Typically, the Fonte is limited to the first two iterations of the sequence; however, the label is a useful one even for extended occurences of the Down 3rd, Up 2nd sequence (which can be a slightly clunky term).
In the key of E minor, the Fonte chord progression would be Em, Am7/C, D, G7/B, C, F#aug7/A, B, Em. That looks quite intimidating! It isn’t particularly useful to think of schemata (such as this Fonte sequence) as chords. Instead, think of these sequences as counterpoint. Each voice moves in its own direction in its own time; yet, when these voices sound together, they create beautiful harmony. Notice also that this Fonte schema has the strong beats as the 6/5 and the weak beats as the 5/3. This gives the sequence stronger sense of direction by using metre to emphasise harmonic tension and release.
Example Realisation
My realisation below contains a mix of two and three voices. I have included small differences in realisation for each usage of the technique in focus (bb. 1-2, 8-9, 16-17, 19-20). Notice that this partimento contains a mixture of figured and unfigured bass. Durante includes figured bass at important areas in the partimento, such as the rule Durante is teaching, and modulations. The absence of figures also highlights what Durante expects students to know when realising this partimento. He expects the student to undestand the chords implied by unfigured basses. This is mixed with the convention of abbreviating figures. Durante does not indicate figures for 5/3 chords and he uses the 6 to indicate 6/3. This may provide another explanation for the absence of some figures. This poses a challenge for modern students who may not be as well versed in figures, and most likely not at all in unfigured bass. This realisation provides one possible harmonisation of the unfigured bass.
This partimento offers a great opportunity for students to practise one of the nicest sequences, the Fonte. Listen to the audio, download the score, play the realisation, and improvise or compose your own!
Bibliography
Gjerdingen, R. (2010). Mozart’s obviously corrupt minuet. Music Analysis, 29 (1/3), 61-82.
Gjerdingen, R. (2016). On the use of (sequences of) 6/5s. Monuments of Partimenti. https://web.archive.org/web/20170711051235/http://faculty-web.at.northwestern.edu/music/gjerdingen/partimenti/collections/Durante/regole/43DurReg/43DurReg.htm

Partimento: A Beginner Method for Classical Improvisation
‘Partimento: A Beginner Method for Classical Improvisation’ book teaches the reader classical improvisation through updating the method of Partimento for the modern student.
During this book, we start by getting to know the basics of music, covered in Stage 1: Prerequisites. Then, from Stages 2-5 we tackle the main ingredients of improvisation (what the 18th century, Neapolitans called Regole, the “Rules”). Finally, in Stages 6-7 we practise improvising with, and without, partimenti. Here are the seven stages below:
Introduction (pp.3-8)
Stage 1 – Prerequisites (pp.9-43)
Stage 2 – Cadences (pp.44-72)
Stage 3 – Rule of the Octave (pp.73-92)
Stage 4 – Sequences (pp.93-137)
Stage 5 – Modulations (pp.138-171)
Stage 6 – Partimenti (pp.172-188)
Stage 7 – Improvise! (pp.189-220)
Conclusion (pp.221-228)
Take your first steps into classical improvisation on the rediscovered path of Partimento.