The Actual vs. Predicted Effects of Intonation Accuracy on Vocal Performance Quality

The belief that intonation accuracy is a key determinant of musical performance quality is ubiquitous in music pedagogy; nonetheless, empirical validation of this belief is lacking. We investigated the effects of intonation accuracy on perceived performance quality and assessed whether music professionals’ beliefs about the importance of intonation are consistent with these effects. In Experiments 1 and 2, participants listened to vocal performances that were in tune, moderately out of tune, or severely out of tune. Only severe mistunings caused decreases in performance quality ratings for intonation insensitive listeners (those who performed poorly on a mistuning detection prescreening). However, both moderate and severe mistunings were detrimental to the ratings of intonation sensitive listeners. These results indicate that moderate mistunings exert a negative influence on the perceived quality of a performance only if the listener can explicitly detect the mistunings. If a listener cannot explicitly detect the mistunings, those mistunings do not implicitly exert a negative influence on the perception of the performance. In Experiment 3, music professionals heard samples of performances from Experiments 1 and 2 in each intonation condition and were asked to estimate the impact of the mistunings on listeners’ ratings of performance quality. Their predictions were compared to the actual performance quality ratings obtained in Experiment 2. Music professionals overestimated the impact of moderate mistunings for both intonation sensitive and insensitive listeners, suggesting that music professionals may hold inaccurate beliefs about the importance of intonation accuracy in vocal performance.