Colloquium: Sensory Dissonance Models

The Colloquium for Interdisciplinary Music Research has started again. We have currently two sub-colloquia, one for empirical music research and another that focuses on music and emotion.

The Empirical Colloquium convened last Thursday to discuss Tuukka Tervo’s work on sensory dissonance models. Sensory dissonance is the sensation of roughness or discord that we can have when hearing two or more notes. The “sum”, or compound of the notes can sound unpleasant or tense, instead of pleasant and clear like in the opposite case of consonance. Traditionally, intervals such as octaves, fifths and fourths have been considered consonant, while sevenths, seconds and even thirds have been dissonant.

There are two aspects in this perception of dissonance, the cultural one (we are used to certain kinds of tone combinations and tuning systems, and judge those we find pleasurable as “consonant”, and those that we find tense or unfitting in the context as “dissonant”) and the sensory, psychoacoustical one. The latter, where the degree of dissonance can be measured from the acoustical components of the sound stimulus and the physical properties of our auditory perception system, was on the table last Thursday.

There are many models of how to calculate how dissonant a certain compound of notes, or a certain passage of music is. This is considered an important factor in how the piece of music would be perceived, remembered or categorised, and therefore an interesting topic for music research and for instance the applied field of music information retrieval.

Tuukka has tested various models of sensory dissonance by comparing their results with the judgements of dissonance made by music students. He used real musical material; chords, drone music and piano jazz, and has now performed the experiment and a preliminary analysis. You can read about both in the embedded presentation. This work is part of Tuukka’s master’s thesis, due for completion next year.