Defining “happy” in happy birthday: Singing accuracy a construct based on range and intervals

Singing in tune, or singing accuracy, is a construct dependent on genre, key selection, singers’ ranges, and listener expectations. But across genres, singers are expected to sing in tune with themselves and with others. Because singing a familiar song may be the most common communal singing situation in the lives of non-professional singers and students, we chose to examine previously reported data on the Happy Birthday song as representative of one typical example of a popular song globally and used in previous research. The participants were adult non-professional singers. We designed a predictive model of performance on the large ascending octave based on initial interval performance, providing implications for music education in children or adults and by exploring variables such as range, voice register, and key modulation. We conclude that while initial performance may predict subsequent performance, features such as singer’s range and starting pitch may also account for variability in individual performance.