Psychology Paradigm Challenge

We’ve been obsessed with harmony for centuries, but it turns out how evenly notes are spaced is what actually makes a chord sound beautiful.

March 23, 2026

Original Paper

Interval Uniformity Predicts Chord Consonance After Controlling for Harmonicity, Roughness, and Familiarity

Amaar M. Chughtai

PsyArXiv · jb372_v1

The Takeaway

We traditionally think musical beauty is about 'harmonicity'—how well sound waves line up. This research shows that our brains also have a hidden preference for 'interval uniformity,' meaning we find chords more beautiful simply if the notes are spread out neatly across the frequency range.

From the abstract

We test whether any structural property of a chord's interval distribution predicts consonance beyond harmonicity, roughness, and cultural familiarity. Log-frequency entropy, a measure of how uniformly a chord's intervals span the frequency range, remains significant (t = 6.10, p < .001; VIF = 1.27) after controlling for all three components in the Bowling et al. (2018) dataset (N = 66 triads). This independence holds across four roughness models, survives after partialling out minimum interval