The Magaloff Project: An Interim Report

Abstract

One of the main difficulties in studying expression in musical performance is the acquisition of data. While audio recordings abound, automatically extracting precise information related to timing, dynamics, and articulation is still not possible at the level of precision required for large-scale music performance studies. In 1989, the Russian pianist Nikita Magaloff performed essentially the entire works for solo piano by Frédéric Chopin on a Bösendorfer SE, a computer-controlled grand piano that precisely measures every key and pedal action by the performer. In this paper, we describe the process and the tools for the preparation of this collection, which comprises hundreds of thousands of notes. We then move on to presenting the results of initial exploratory studies of the expressive content of the data, specifically effects of performer age, performance errors, between-hand asynchronies, and tempo rubato. We also report preliminary results of a systematic study of the shaping of particular rhythmic passages, using the notion of phase-plane trajectories. Finally, we briefly describe how the Magaloff data were used to train a performance rendering system that won the 2008 Rencon International Performance Rendering Contest.

Acknowledgements

We hereby want to express our gratitude to Mme Irène Magaloff for her generous permission to use this unique resource for our research. This work is funded by the Austrian National Research Fund FWF via grants P19349-N15 and Z159 (‘Wittgenstein Award’). The Austrian Research Institute for Artificial Intelligence acknowledges financial support from the Austrian Federal Ministries BMWF and BMVIT.

Notes

¹Information available through the program archive of the Wiener Konzerthaus, http://konzerthaus.at/archiv/datenbanksuche

²Each note on- and offset is captured with a temporal resolution of 1.25 ms. The velocity of the hammer at impact is converted and mapped to 128 midi loudness values. See Goebl and Bresin (2003) for details.

³See http://www.visiv.co.uk

⁴At age 77, Alfred Brendel performed one solo program and one Mozart Concerto for his last season in 2008.

⁵Of course, Magaloff's repertoire might have been broader in younger years, which would then indicate otherwise. A systematic comparison of earlier concert seasons and all concert in 1989 would provide further insights into that particular aspect.

⁶Arrau (recorded 1956), Ashkenazy (1975), Backhaus (1928), Biret (1990), Cortot (1934), Gavrilov (1985), Giusiano (2006), Harasiewicz (1961), Lortie (1986), Lugansky (1999), Magaloff (1975), Magaloff (1989), Pollini (1972), Schirmer (2003), Shaboyan (2007), and Sokolov (1985).

⁷A basic tempo value was estimated by the mode value, the most frequent bin of an inter-beat interval histogram with a bin size of 4% of the mean inter-beat interval.

⁸These considerations are based on the underlying assumption that the difficulty of a piece increases with the tempo. This is not universally true. However, for the pieces in question—the fast pieces of the Études—the assumption seems warranted.

⁹Note that the clustering was not done for any analytical purpose, only to summarize the trajectory data succinctly.

¹⁰We assume that the highest pitch at any given time is the melody voice of the piece. This very simple heuristic is certainly not always true, but in the case of Chopin is correct often enough to be justifiable.

¹¹According to Narmour's theory, ‘musical closure’ is achieved when the melodic progression arouses no further expectations in the listener's mind. The emerging segmentation of the score is comparable to a crude phrase structure analysis.

¹²See http://www.renconmusic.org/icmpc2008/autonomous.htm

¹³We only have access to the audience evaluation scores for the RENCON Award. There, YQX scored a total of 628 points, compared to 515 points scored by the second-ranked system.