Analysis of Intonation Trajectories in Solo Singing

We present a new dataset for singing analysis and modelling, and an exploratory analysis of pitch accuracy and pitch trajectories. Shortened versions of three pieces from The Sound of Music were selected: “Edelweiss”, “Do-ReMi” and “My Favourite Things”. 39 participants sang three repetitions of each excerpt without accompaniment, resulting in a dataset of 21762 notes in 117 recordings. To obtain pitch estimates we used the Tony software’s automatic transcription and manual correction tools. Pitch accuracy was measured in terms of pitch error and interval error. We show that singers’ pitch accuracy correlates significantly with self-reported singing skill and musical training. Larger intervals led to larger errors, and the tritone interval in particular led to average errors of one third of a semitone. Note duration (or inter-onset interval) had a significant effect on pitch accuracy, with greater accuracy on longer notes. To model drift in the tonal centre over time, we present a sliding window model which reveals patterns in the pitch errors of some singers. Based on the trajectory, we propose a measure for the magnitude of drift: tonal reference deviation (TRD). The data and software are freely available. 1