If you hear the opening of a song, you can usually tell if it will be a happy or sad song. But which notes or chords are tied more closely to emotions? A team of researchers linked the emotion of lyrics to the musical notes themselves. The study published in Royal Society Open Science is cleverly named after lyrics from Leonard Cohen’s song Hallelujah. They confirmed that major chords are tied to happiness, and minor chords to sadness. Additionally, they found that one chord, in particular, is linked to happy music.
The researcher took 90,000 guitar songs in English that had tabs and lyrics from ultimate-guitar.com. Next, they compared the connotation of the word with the chord played at the same time. To do this they used a data set that ranks 10,222 common English words as either negative or positive. They were ranked according to the valence; a higher valence means a more positive or attractive emotion. The scale ranges from 0.0 (the most negative) to 9.0 (the most positive).
The results suggest that minor chords are connected with more negative words, while major chords are associated with more positive words. However, seventh chords (comprised of three notes with an additional note on top that alters the sound) were the happiest of all and were used the most often to convey a positive feeling. All three types, Minor 7th, Major 7th, and dominant 7th, have a higher valance than major chords.
The researchers analyzed the data for more general trends as well. They included a geographical comparison, though it is rather limited considering that they only looked at English songs. Songs from Asia and Australia were the most positive, while songs from Scandinavia were the darkest — due to the popularity of metal music there.
Music has been steadily becoming more depressing since the 1950s, the authors report, however songs are becoming happier from 2010 on. If you want some feel-good music, you should listen to religious music or 60s rock because they ranked the most positive. Unsurprisingly, punk and metal fell at the other end of the spectrum.