Music Theory for Harmonica Players

Music Theory for Harmonica Players Part 4 – Scale Degrees

Last time we defined the major scale and discussed how it’s built. Now we’re going to add another way of thinking about and referring to notes in the scale.

Take for example the G major scale. Remember that the major scale is built using notes from the chromatic scale in this sequence:

whole-tone, whole-tone, semi-tone, whole-tone, whole-tone, whole-tone, semi-tone

Here’s that piano keyboard again:

Notes on Piano Keyboard

Using the pattern we find the G major scale looks like this:

G A B C D E F# G

The term Scale Degree refers to a given note’s position in the scale rather than the note itself. We use numbers like this:

G A B C D E F# G
1 2 3 4 5 6 7  8

So we can see that C, for example, is the 4th note of the scale. This is referred to as the 4th, fourth or just the number 4. D is the 5th note of the scale (fifth, 5) and so on.

The first note in the scale is usually referred to as the root or tonic.

The 8th note is also G but it sounds higher in pitch than the first G. This is called the octave. It’s the same note but eight scale degrees higher (octave is a latin word relating to the number eight). Played both together they sound perfectly in tune.

If you were playing in G and decided to stick a Bb in you would call that a flat 3rd (b3) since it’s one semi-tone below the third. Similarly if you played an F it would be a flat 7th (b7) and so on.

This is all quite theoretical but it’s an important concept to start thinking about. It enables us to discuss scales in a generic way without having to memorise 12 different scale spellings, it’s a useful shorthand for communicating with other musicians and it’ll be essential when we start looking at building chords.

Next time we’ll take a closer look at our harmonica and they way it’s note layout works.