Composers have, over the ages, chosen keys to ‘flavour’ their music in a particular way. So which are the most characterful, and who has used them to their greatest effect? Ivan Hewett delves into his scores to find out

By Ivan Hewett

Published: Wednesday, 15 February 2023 at 12:00 am


What is a musical key?

Every piece of music – be it a pop or folk song, a string quartet, a violin concerto or a operatic overture – is in a certain key. But what do we mean by this? Let’s first look briefly at what a key is.

Essentially, a key is the principal group of notes that gives any piece of music its harmonic building blocks. The main notes used in a song are usually all from one particular scale, and this is where we name the song’s key from.

The key that most music learners come across first is the key of C major. That’s because the scale of C major uses no sharp or flat notes – it simply goes C, D, E, F, G, A, B, C. That means no need to use the black notes on the keyboard – only the white ones.

A song that only uses notes from the C major scale will (usually) be in the key of C major.

In fact, each key signature (in this case, no sharps or flats) is shared by two keys: one major, one minor. C major shares its key signature with A minor.

But there are plenty more keys than these two. And different keys seem to have different characteristics, so that a composer is likely to choose a different key for writing a piece of joyous or festive music, than for something a little more melancholy or otherworldly.

Let’s take a look at some of the most common keys and their sonic attributes or moods.

How did composers use different musical keys?

For centuries, people have claimed that musical keys have special qualities of their own. In the Baroque era, whole treatises were written on the subject. It’s been said that E flat major is warm, D flat major is spooky, and E flat minor is seriously unhinged.

Keys have colours too, apparently: E major has been described as sapphire blue, A flat major as purple, and D major as golden. Composers and performers who experience the condition of synaesthesia will understand this well.

All hokum, say the sceptics. They’ll point out that for every person who thinks C major is chalky white, there’ll be another for whom it’s emerald green. They’ll remind us that though keys may have had distinct ‘colours’ in the era before Bach, when odd, exotic tunings abounded, every major and minor key now sounds – thanks to equal temperament – absolutely identical to every other.

As for the expressive qualities of keys, these vary hugely from one composer to the next. F sharp major had a special significance for Scriabin, C minor had a special flavour for Beethoven. But F sharp major sounds very different in Tchaikovsky and Bach, and Shostakovich’s C minor isn’t like Beethoven’s. 

Check out our guides to the lives and times of all the great composers

All this is undeniable, but it’s not the whole story. The fact that earlier composers thought of keys in specific ways surely affected the way they composed in them. And if we think of G minor as tragic largely because Mozart had a special feeling for that key, isn’t that enough? Won’t that affect the way we hear that key in other contexts?