Scales - Fundamentals of Music Theory
If you have read the earlier sections you may have already seen references to scales on several occasions. That is because it is very difficult to discuss even the basics of music theory without a mention of scales. They are a vital, fundamental element of the language of music. Not only do scales allow us to set a mood for our music (each scale has its own character), they also facilitate collaboration with other musicians.
What are Scales?
In essence a scale is a template which, along with a key (root note), allow us to select a collection of specific notes. There are different methods of describing these templates. But before we get into that, let's take a look at our first scale.
The Chromatic Scale
The most straightforward of scales, the Chromatic scale represents all of the notes available to us in modern western music with each note separated by a semitone.
C, C♯/D♭, D, D♯/E♭, E, F, F♯/G♭, G, G♯/A♭, A, A♯/B♭, B, C
Remember from the introduction to music theory section, we generally use the sharp name when ascending up a sequence of notes, and the flat name when descending down a sequence of notes. So the ascending chromatic scale would look as follows:
C, C♯, D, D♯, E, F, F♯, G, G♯, A, A♯, B, C
Scale Patterns
Scale patterns are probably the most common way of describing a scale's template and consist of a sequence of intervals that specify the distance from the current note to the next note. That distance is measured in semitones and tones (two semitones) and is commonly abbreviated to S and T respectively.
Note: As mentioned previously, you may also see these intervals described as half steps and whole steps, in which case you may also see scale patterns made up of H and W.
Let's say we want to know the notes of the G Major scale. We know that our key is G, so this is our root note and starting point. So firstly we will rearrange the ascending chromatic scale example from above so that it starts from G.
G, G♯, A, A♯, B, C, C♯, D, D♯, E, F, F♯, G
The Major scale pattern is T, T, S, T, T, T, S. Applying this pattern, beginning with our root note, we can find the rest of the notes of the scale through to our octave note (same as our root note but one octave higher). So if we count two notes up (T) from our root note of G, we get to A, our 2nd note. Looking back at the pattern we can see we need to count another two notes up (T) from our 2nd to get to B, our 3rd note. Next up we have an S, so we only count one note up from our 3rd to get to C, our 4th. Continuing with this pattern we get the following:
G, G♯, A, A♯, B, C, C♯, D, D♯, E, F, F♯, G
Once you know the pattern of a scale, you can apply it to any other key. Let's try a B Major scale this time.
B, C, C♯, D, D♯, E, F, F♯, G, G♯, A, A♯, B
As each scale has a unique pattern, some of the notes from any two different scales in the same key will also be different. This is what gives each scale its character. Let's compare the above with a B Natural Minor scale which has a pattern of T, S, T, T, S, T, T.
B, C, C♯, D, D♯, E, F, F♯, G, G♯, A, A♯, B
We can see that whilst both scales share the notes B, C♯, E, F♯, B, the B Natural Minor scale has a different 3rd (D), 6th (G) and 7th (A).
As we can see, scale patterns are very useful, however they aren't the only way to describe the structure of a scale.
Scale Degrees
Scale degrees tell us where a particular note fits into the sequence of notes within a scale. Starting with the 1st note, also known as the tonic or root note, then progressing through the sequence of 2nd, 3rd, etc up to the 7th, then tonic again (or octave). Some of these numbers can also be preceded by a ♭ (flat) symbol which shows that particular interval is of a minor quality (see the earlier section on intervals). If there is no preceding ♭ symbol, the degree is considered to have a major or perfect quality. Let's see some examples.
A Major scale is made up of only major and perfect intervals and so none of the degrees have a ♭ symbol.
1, 2, 3, 4, 5, 6, 7, 1
A Natural Minor scale however does contain some minor quality intervals.
1, 2, ♭3, 4, 5, ♭6, ♭7, 1
So we can see this scale has a minor 3rd, 6th and 7th.
You may also see scale degrees identified by roman numerals, especially when used to describe a chord built on a scale.
I, II, III, IV, V, VI, VII, I
This however, isn't the whole story for scale degrees. They also have names. Whilst not widely used these days, you will likely need to learn them if you plan on taking any music theory examinations.
| Degree Number | Degree Name |
|---|---|
| 1 or 1st | Tonic |
| 2 or 2nd | Supertonic |
| 3 or 3rd | Mediant |
| 4 or 4th | Subdominant |
| 5 or 5th | Dominant |
| 6 or 6th | Submediant |
| 7 or 7th | Submediant (Whole tone below the tonic) or Leading tone (Semitone below the tonic) |
| 1 or 1st (8 or 8th) | Tonic (Octave) |
Whilst the degree numbers can describe quality i.e. whether the degree is flat or not, the degree names, with the exception of the 7th, do not give any indication of quality and so aren't a great method to calculate which notes are in a given scale and key.
Scale Intervals
As scale patterns describe the distance between each note, scale intervals describe the distance from the tonic (root) note of a scale to each other note in the scale. You can think of scale intervals as a combination of the degree number and word to describe its quality i.e. minor, Major, Perfect, diminished or Augmented. We have a dedicated section on intervals so we won't go into too much detail here. However, knowing how many semitones make up a specific scale interval helps you to construct a scale. They are also very useful in understanding chord construction, for example a minor 3rd interval is 3 semitones from the tonic, and a Major 3rd interval is 4 semitones from the tonic.
Scale Types
There are many different scales and modes, however they all fit into one type or another based on how many notes the scale contains.
Chromatic Scale
We have already mentioned the Chromatic scale above which consists of all twelve notes available in common western music based on something called 12 equal temperament. In short this means dividing an octave into twelve, equally spaced notes.
C, C♯/D♭, D, D♯/E♭, E, F, F♯/G♭, G, G♯/A♭, A, A♯/B♭, B, C
Heptatonic Scales
A Heptatonic scale consists of seven notes. Many different scales from around the world can be classed as Heptatonic including scales that are also referred to as Diatonic scales, and some other well known scales like the Harmonic Minor scale and the Melodic Minor scale.
Diatonic Scales
Diatonic scales also consist of seven notes and so are also classed as heptatonic scales. However they also conform to a set of rules that distinguish them from other heptatonic scales.
A diatonic scale must:
- contain five whole tone intervals within an octave
- contain two semitone intervals within an octave
- In addition the two semitone intervals must be separated by either two or three whole tones (four or six semitones)
Some examples of diatonic scales include the Major scale and the Natural Minor scale (see below) and the seven diatonic modes, two of which are the origins of those scales. Note that the Harmonic Minor scale and the Melodic Minor scale are not technically diatonic despite having seven notes because they don't conform to the aforementioned rules of a diatonic scale.
Pentatonic Scales
Pentatonic scales work with even less notes than diatonic and heptatonic scales, consisting of only five notes. Pentatonic scales have been around for a very long time and were independently discovered and used by many different cultures all over the world. Modern examples include the Minor Pentatonic scale and the Major Pentatonic scale.
Other Scales
There are of course other scale types based on different numbers of notes such as Octatonic scales with eight notes and other even less common scales based on four notes or less. One other notable type of scales are the Hexatonic scales consisting of six notes. These include the Whole tone scale, various scales popular in folk music, and of course the Minor Blues scale which is based on the five note Minor Pentatonic scale with an added flat fifth, and the Major Blues scale which is based on the five note Major Pentatonic scale with an added flat third.
Scale Relationships
Both the Major and Minor scales can be related to each other in several different ways.
Relative Minor Scale
Every Major scale in a given key has a relative Minor scale key. The relative scale shares all the same notes as source scale but starts from a different tonic/root note. In the case of the relative Minor scale, this tonic is the 6th degree of the Major scale. Let's take the C Major scale for example (This is a nice simple example as we only need the white keys on a piano). If we count up to the 6th degree of this scale we find A.
C, D, E, F, G, A, B
If we now list the same notes but starting from the A, we have the A Natural Minor scale.
A, B, C, D, E, F, G
Relative Major Scale
So, based on what we have just learned, it figures that each Natural Minor scale key must have a relative Major scale key. Using our previous example, but this time starting out with the A Natural Minor scale, we need to count to the 3rd degree and then re-order the notes.
A, B, C, D, E, F, G
This gives us the C Major scale.
C, D, E, F, G, A, B
Parallel Major and Minor Scales
A parallel scale is one that shares the same key but uses the opposite scale pattern to the source scale. For example the parallel minor scale of C Major is C Natural Minor and vice versa.
Common Scales
Major Scale
The most common of all scales, certainly in western music, has to be the Major scale. A diatonic scale with seven notes, its origins lie with the church modes, in particular the Ionian mode, but more on those later. The scale has a cheerful sound thanks mostly to its Major third interval and can be heard in everything from baroque and classical music through to virtually every pop song. This is normally the first scale you will learn as it consists of just the white keys on a piano keyboard when starting from C. This produces the scale pattern T, T, S, T, T, T, S. As with all scales though, this pattern can of course be transposed to apply to any other key which would then require the use of some of the black keys.
Natural Minor Scale
The Natural Minor scale too has its origins in the church modes with the Aeolian mode. Again it involves only the white keys on a piano keyboard if starting from A which produces the scale pattern T, S, T, T, S, T, T. The minor scale has a more sombre quality due to its minor third interval but this can also add beauty and deeper emotion to a piece of music. It is worth giving an honourable mention here to another two “minor” scales that were derived from the Natural Minor scale. These are the Harmonic Minor scale with its raised 7th degree, and the Melodic Minor scale which has both a raised 7th and 6th degree (although it reverts to Natural Minor scale when descending).
Major and Minor Pentatonic Scales
A list of commonly used scales wouldn't be complete without both the Minor Pentatonic scale with a pattern of TS, T, T, TS, T and the Major Pentatonic scale with a pattern of T, T, TS, T, TS. Most blues and a lot of rock and jazz music utilises either or both of these scales, in particular for solos and improvisation over related diatonic chords.
Resources
If you are looking for information on a specific scale and key, check out our Music Theory Scales section and just select the scale and key you need for a detailed breakdown. And if you want to view scales on your preferred instrument of choice, each instrument section includes a scales section such as Piano Scales, Guitar Scales, Bass Scales, etc.
