An Accent-Based Approach to Automatic Rendering of Piano Performance: Preliminary Auditory Evaluation

We are exploring the relationship between accents and expression in piano performance.
Accents are local events that attract a listener’s attention and are either
evident from the score (immanent) or added by the performer (performed). Immanent
accents are associated with grouping (phrasing), metre, melody and harmony.
In piano music, performed accents involve changes in timing, dynamics, articulation,
and pedalling; they vary in amplitude, form, and duration. We analyzed the
first eight bars of Chopin Prelude op. 28 n. 6. In a separate study, music theorists
had marked grouping, melodic and harmonic accents on the score and estimated the
importance (salience) of each. Here, we mathematically modeled timing and dynamics
in the prelude in two ways using Director Musices (DM) – a software package
for automatic rendering of expressive performance. The first rendering focused on
phrasing following existing and tested procedures in DM. The second focused on accents
– timing and dynamics in the vicinity of the accents identified by the theorists.
In an informal listening test, 10 out of 12 participants (5 of 6 musicians and 5 of
6 non-musicians) preferred the accent-based formulation, and several stated that it
had more variation of timing and dynamics from one phrase to the next.