Timbre Features and Music Emotion in Plucked String, Mallet Percussion, and Keyboard Tones

Music conveys emotions by means of pitch, rhythm, loudness, and many other musical qualities. It was recently confirmed that timbre also has direct association with emotion, for example, that a horn is perceived as sad and a trumpet heroic in even isolated instrument tones. As previous work has mainly focused on sustaining instruments such as bowed strings and winds, this paper presents an experiment with non-sustaining instruments, using a similar approach with pairwise comparisons of tones for emotion categories. Plucked string, mallet percussion, and keyboard instrument tones were investigated for eight emotions: Happy, Sad, Heroic, Scary, Comic, Shy, Joyful, and Depressed. We found that plucked string tones tended to be Sad and Depressed, while harpsichord and mallet percussion tones induced positive emotions such as Happy and Heroic. The piano was emotionally neutral. Beyond spectral centroid and its deviation, which are important features in sustaining tones, decay slope was also significantly correlated with emotion in non-sustaining tones.