Theory of Scales

If you would like information on the practical exam requirements regarding scales, click here.

Scales are an arranged order of notes much like the alphabet is a list of letters in the language that we use. To a composer, scales are like the colours on a palette for the artist to paint with. From scales which help to define a key, arpeggios and chords are built giving harmonic structure to a piece of music. Most pupils when learning to play an instrument groan at having to play scales and arpeggios. Once you understand their relationship to the key signature, with a bit of thought, they really are quite easy to play.

There are many types of scales. Below are a few examples.

• Major
• Harmonic Minor
• Melodic Minor
• Chromatic
• Natural minor
• Pentatonic
• Whole Tone
• Blues
• Diminished

Each type of scale will be built in the same way. For example, the second note of a C Major scale will be as far from the first note as the second note of a D major scale is the first note. Likewise the same is true for the other scales. When working out the notes of a scale, there are two ways that I recommend tackling it. With the less common scales like the Blues or Pentatonic or scales that follow a set pattern like the chromatic or whole tone, learn the interval or gap between each degree of the scale. With the more common scales, like the majors and minors, learn the key signature. It is easier to learn that D Major has two sharps (F# & C#) than to learn the eight notes of the scale. Below are some examples of how the scales are constructed. T= Tone, ST= Semitone and T½ = a Tone and a half i.e. Three semitones.

Major: T T ST T T T ST
Harmonic Minor: T ST T T ST T½ ST
Melodic Minor: Ascending- T ST T T T T ST
Descending- T T ST T T ST T
Chromatic: Each note is one semitone from the next
Natural Minor: T ST T T ST T T
Pentatonic: T T T½ T T½
Whole Tone: Each note is one tone from the next
Blues: T½ T ST ST T½ T
Diminished: either T ST or ST T repeated as necessary

In working out the keys to a scale (Major and minor), follow the procedure in the Key Signatures chapter. When working out minors, after working out the key, note that the sixth and seventh degrees of the scale will need altering.

Harmonic
Raise the seventh note one semitone.
Melodic
Ascending, raise the sixth and seventh note by a semitone.
Descending, Go down the scale according to the key signature, i.e. not raising the sixth and seventh notes .

Natural Minor
Note that there are no accidentals in this scale. It goes with the key.