American statistician have analysed 120,000 pieces of music and come to the conclusion that the happiest sounds in music – the minor and major 7th chords – are dying out. And lyrics are becoming sadder since the 1950s.
Pop songs are usually written using a mixture of major and minor chords. In the 1950s the four-chord sequence often featured in doo-wop music was very popular. A major chord followed by its relative minor, then up to the subdominant 4th (or its relative minor) before moving to the dominant fifth usually with a 7th. e.g. C – Am -F – G7 or C – Am – Dm -G7.
Think of songs like “Blue Moon“, or “Where have all the flowers gone“. And more recently Wham’s Xmas song “Last Christmas” which uses only those four chords throughout the song.
Generally speaking minor chords sound sadder than major chords. Apparently 60 years ago the dominant 7th chord outnumbered minor chords. FYI a dominant 7th chord is a major chord with a minor 7th on top of it e.g. C – E – G – Bb. Think of white piano keys. Middle C (Root) then 2 keys up to E (major 3rd) then two more keys up to G (Major 5th) then miss next white key and add next black key Bb (minor 7th).
I think that could be due partly to the fact that dominant 7th chords are frequently used in what are called turn-arounds i.e. the music at the end of each verse which leads into the next verse. Dominant 7th chords have a tension which needs resolving by moving to a major (or minor) chord. Think of Roy Orbison’s “Dream Baby” which is played with dominant 7ths crying out for resolution on the last line of each verse.
Also many songs written in a “twelve bar blues” format would feature the dominant 7th e.g. “Lucille” or “What’d I say“.
Perhaps surprisingly what the scientists found was that the chords most associated with upbeat words were minor 7th chords i.e. like a dominant 7th but with a flattened 3rd e.g. C – Eb – G – Bb. These were widely used in soul and disco music in the 1970s. The major 7th chord was also popular at that time.
They say that music became grimmer since guitar music became popular although that might be changing a little now. And with that the increase in the use of minor chords, the huge decrease in the use of dominant chords (down from 10% to 1% since the fifties) and the disappearance of the major 7th chord.
The major 7th is a beautiful chord with a bitter sweet dissonance as the major 7th note clashes with the root note e.g. C – E – G – B. You can hear it at the beginning of Chicago’s “Colour my world”, and in the Beatle’s song “Misery” as they sing that word.
You’ll hear a combination of major and minor 7th chords in Glen Campbell’s “By the time I get to Phoenix” and in “Valerie” by the Futons and Amy Winehouse.
And in jazz standards it’s a common feature e.g. “Every time we say goodbye”
So let’s not write these chords off just yet. Leonard Cohen knew what he was talking about in “Hallelujah” and what do statisticians know about music anyway?