Some of the questions we receive about pianos surprise us. Yes, we expect the questions about choosing between a new and a used piano. Or how often a piano really needs to be tuned. Yet it’s certain questions that are unexpected, and the more we think about them, the more we realize how complex they really are. Take this one for instance.
Why are there black and white keys on a piano?
At first glance, one of the easiest answers would be that by combining the two keys, it makes the keyboard more functional. If there were only white keys, you would have to start at the bottom and count up to find the keys needed to begin and play a song. By adding the black keys, it gives you a visual cue or repeating patterns to help you stay on track as you play.
But that’s a simple answer. And as it turns out, there is a more complex, historic answer as well.
When you look at the keyboard, by combining the black and white keys, they are laid out in a repeating pattern of groups of two black keys and groups of three black keys. When played, the white keys form a C major scale in a series of half steps – two keys together, one key between. When you play the scale from C to C, you’ll have a perfect set of twelve pitches – all half steps – that create the perfect pattern for most of the music we listen to today.
If you use only the white keys, it gives you all of the notes of the diatonic scale, which means that by transposing to C major, you can play any major key melody using only the white keys. And in fact, if you head back to the 13th century, you will find that most keyboards were white key only, with no “black keys” at all. Most religious music of the time only used C major scale pitches, so it was easy to compose on these keyboards.
Music changed when it began separating from the church, and music became more improvisational in the process. Different scales were run, and experimentation begun, which started creating faster pieces of music that became impossible to ignore the key signature sharps or flats. When people began valuing having a perfectly tuned chromatic notes that could easily be played at higher speeds, the keyboard changed in order to keep up with the demands of the music being created. While experimentation has continued throughout the centuries, this became the perfect – or the standard – in all keyboards, and it’s what we still use today.
Have any other questions about how the piano works? We’d love to hear from you.