The partimenti of Nicola Sala (1713-1801) focus more on counterpoint than pedagogues from the Durante schools of Partimento. Sala teaches invertible counterpoint through presenting themes in the bass followed by their countersubject (which he sometimes marks with a Signa Congruentia ‘:S’ or ‘S:’ (Van Tour, 2017, Introduction)). The theme (interesting) must be played over the countersubject (boring) (Gjerdingen, 2010, p. 46). The reverse is also true, the countersubject must be played over the theme. If the partimento begins with the theme in the bass, then the realiser must look ahead to where the theme likely finishes and the countersubject starts. Then, the realiser must play this countersubject (which may require transposing) over the theme in the bass. Once the countersubject takes over in the bass, the realiser must remember the theme from the left hand, and play it over the countersubject. This applies throughout the partimento. Themes and countersubjects are frequently presented in different keys, requiring transposition for the realiser.
As with every partimento, register is important. The theme and countersubject should be an appropriate distance apart – avoiding unison intervals where possible as the intention is for independent melodic lines. Were there to be too many unison intervals, the independence of the melodic lines could be lost. Furthermore, as partimenti are generally realised at the keyboard, unison intervals are awkward to play, particularly without a sustain pedal.
The understanding of the countersubject and the theme involves the student to pre-study the partimento. The realiser may choose to write any label which will help their realisation. I have added annotations to the partimento from Sala below to show the reader how I understand the makeup of the partimento. The labels I have used indicate key, theme or countersubject, and modulation method e.g. “I-IV using ④”. Other labels may help the realiser such as schema, scale degrees or pop chords. Just a point on notation, Sala uses the slur to indicate a harmony which should be sustained across all of the notes within the slur. As Van Tour (2017, Introduction) writes, “a slur is used as a signal not to change harmony”.
In my realisation, I have changed between three parts and two parts. I usually dropped to two parts during the right hand theme to avoid complexity in the right hand and to to maintain the single voice in the bass. This also allowed the theme to stand out and for the modulatory passages to have a fuller, richer sound. I have also chosen not to use the tenor voice in bar 14-16 as an indication for the third part throughout every iteration of the countersubject. This was more of a musical decision than a contrapuntal one, I preferred the third rather than the octave as the third voice.
These partimenti realisations benefit from keeping voices simple. Were realisations to be too florid, they may undermine the theme in the bass (unless the bass theme were also to be changed), and risk encountering voice leading issues. Considering that realisations should be realised without being written, then simpler voices allow clearer memorisation. Correct voice leading is more important at this stage than florid passagework.
Gjerdingen, R. (2010). Partimenti written to impart a knowledge of counterpoint and composition. In D. Moelants & K. Snyers (Eds.) Partimento and Continuo Playing (pp. 43-70). Leuven: Leuven University Press.
Van Tour, P. (2017). The 189 partimenti of Nicola Sala: Volume 1 partimenti Nos. 1-100. Uppsala Universitet.