According to Western musical tradition, chords sound beautifully ’consonant’ when the frequencies of the individual tones have a low, simple ratio. For example when that ratio is 2:1, or 3:2. Deviations from this are thought to make for unpleasant, dissonant chords. It’s been argued by the Ancient Greek philosopher Pythagoras that this ‘rule’ of musical harmonies is universal. In other words, it should apply to chords played on all instruments, in all cultures.

But a recent paper in Nature Communications suggests that this is not correct. In fact, through a series of online studies that involved more than 4,000 people and 235,440 individual musical judgements, Raja Marjieh and colleagues found some discrepancies between what has long been assumed to underpin consonance and what listeners felt actually made a chord sound pleasant.

From an analysis of reports from participants from South Korea as well as the US it emerged that while chords from non-Western instruments did not follow the ‘rule’ of simple mathematical tone ratios at all, they could still sound pleasant.

According to the researchers, if more Western musicians used instruments from non-Western cultures, they could “unlock a whole new harmonic language that people intuitively appreciate.”