There is a passage in the third movement of Joaquín Rodrigo’s Sonata Giocosa that I have always found interesting:
Joaquín Rodrigo: Sonata Giocosa, mvt. III, mm. 137-144
The passage, like the rest of the work, is tonal. Each beamed group of eighths suggests a chord; the first and last note of each group belong to the chord, and the second note of each group is an appoggiatura to the last. These chords, in turn, form a clear, tonal harmonic progression. Clear as it is on paper, it is however difficult to understand these harmonies when listening to the work. The reason is that the appoggiaturas rarely sound as such. Displaced at a higher register, those notes acquire a prominent role and render the harmony ambiguous. Furthermore, their prominence is usually strengthened by interpretations that accent them and/or let them ring over their resolution notes, which blur their melodic function. Since the piece moves quickly, there is barely enough time to process the appoggiatura-resolution pairs, which are rather processed as some sort of false relations. And thus the work sounds suddenly “atonal” for a few seconds. I would imagine this is particularly the case for first-time, untrained listeners.
We should then downplay the appoggiaturas (they will sound clearly regardless, since they appear by themselves on a high register), and of course damp them toward the last note of each group. I would also consider two alternate voicing options: (1) to move the last note of each group an octave higher (Figure 2) or (2) invert each group, so as to retain the shape and “gesture” of each group but feature the appoggiaturas on the lower octave, where they are less prominent (Figure 3). I encourage you to try these; even if you keep the original version in performances, they might bring you a new insight for the passage.
On a related note, this passage has led me to write an article about the dissonances in Rodrigo’s guitar music. It will be published in the upcoming Soundboard, Vol. 41, No. 3.