Music Theory De-mystified Blogspokes of a scale

8. What Is A Scale?

This post is one of a 2-part series of free basic music theory lessons on my blog, musictheoryde-mystified.com. You can see the complete list here. Please feel welcome to make a comment or ask a question.

If you’re looking for the quick answer, scroll down to the summary.

A scale is both a sequence of note pitches you can play by itself as a simple melody (usually for practice) and the basis of a piece of music.

In 1 Note Names, Semitones and Octaves, we saw that there are 12 different musical note pitches within an octave, each 1 semitone apart. We also saw that there are only 7 letters used to name music. On a musical stave there are also only 7 pitch positions per octave, one for each letter.

This is because most music in Western culture is usually made up using only 7 of the 12 notes at a time, the eighth note being the octave (hence the name “octave”). Such a selection of notes is called a scale. The first note of a scale is the reference note for music written in that scale.

Note: It is possible for a scale to have more or less than 7 notes (such as the 5-note pentatonic blues scale) but the vast majority of music in Western culture, both historically and in modern times, is based on 7-note (heptatonic) scales.

How Far Apart Are Scale Notes?

For 7 notes to make up an octave (12 semitones), the notes can’t all be spaced evenly. Most of the notes are 2 semitones apart, but there are two pairs which are only 1 semitone apart. For example, let’s look at the naturals; the notes that have just a letter as their name.

The naturals from A to A with note spacing in semitones

C major

Although the notes are named starting on A, C is the starting point for the most common scale of all, C major. We’ll talk about major and minor shortly, but for now, let’s look at the notes starting on C.

The naturals from C to C with note spacing in semitones

C major is made up of the naturals starting on C. We can see that C to D is 2 semitones, as is D to E, then E to F is only 1 semitone, etc. This is quite easy to see on a piano keyboard, as the named notes are the white keys and the others, the black keys. The interval from one key to the next is 1 semitone, whether between adjacent white keys or between a white key and an adjacent black key. (The staggered layout of a piano’s keys is for practical reasons- so one hand can span an octave).

Note: In scales, the intervals marked as 2 semitones are usually called a “tone” rather than “2 semitones”. Other schools use the terms ”steps” and ”half-steps” for the 2- and 1-semitone intervals between the notes of a scale.

In this blog I will always name intervals by semitones or by their musical interval name. For my reasons, see A Story Of Tones And Semitones.

The Root Note

When we play a scale, we usually emphasise the first and last note, in this case, C, by playing those notes louder, longer or both. Playing a scale in this way helps us feel that the starting/ending note is the home note and that the other notes either lead away from that note or towards it.

The first note of a scale is called the root note or tonic and it is the most important note in a scale. The root note represents home in a musical journey and the start of the pattern of intervals from note to note that defines the scale.

Modes

Let’s play a scale using only the naturals, from C to C and back.

Now let’s play the same notes but starting on a different root note, such as A. We’ll play A to A and back.

Sure, one was slightly higher than the other, but did you notice a difference in character/flavour/mood? Have another listen…

… (I’ll wait)…

This difference in character is even more noticeable in a real piece than just a scale.

Now let’s compare the spacing of the notes.

Notice the difference in the order of the 2’s and 1’s in relation to the root note? It is this pattern that determines the scale’s character.

The pattern of intervals that determine the note spacing of a scale is called a mode. When using just the naturals, each time we start on a different note, the pattern of note spacing is different. There are 7 different naturals, each of which is the root note of a mode. Of the 7 modes produced, six are quite common in various genres and one, the one starting on B, is seldom used (but that’s the subject of another post).

Earlier on, I called the first scale, starting on C, C major. The term major refers to the mode. Major is the most commonly used mode in modern Western music, hence the name. The one on A is called A natural minor or just A minor for short. Minor scales are usually used in a slightly different way to major in that there are two popular variations on the natural minor. We’ll look at how these variations are used in part 2 of this course so for now we’ll use the natural minor as our minor example.

The major and natural minor modes are also known by Greek names based on modes in the renaissance era.
Major = Ionian mode. Natural minor = Aeolian mode.

What About Keys?

You’re more likely to hear people talk in terms of keys rather than scales and modes. A key is simply the notes of a scale when they are rearranged to make music.

For instance, any music which is based on the scale of C major is in the key of C major.

The major or minor (or any mode, for that matter) can be made to start on any root note. The major mode on D is called D major. The minor mode on F is called F minor. We’ll look at how this works in coming posts..

Scales and melodies

We can tell the difference between C major and A minor when we play the scale because we’re emphasising the root note – by playing it first, last and longer than the other notes. Furthermore we can hear the progression of ascending or descending notes arrive on the root note. But how can we recognise the mode when the notes are all mixed up in a melody?

It’s all about being able to recognise the root note.

Melodies rely on a range of techniques to highlight the root note including those I’ve just mentioned. A melody isn’t a random selection of notes. The structure of the phrases that make up a melody and the relative length and strength of notes all contribute to our ability to recognise the root note as home. Some of these techniques are mentioned in a little more detail in How Can We Tell Which Key We’re In?

Summary

A scale is a selection of (usually 7) pitches within an octave, which form the basic pitch elements of a piece. The notes can be played at any octave.
The root note or tonic is the first note of the scale and the reference/ home note for music written using that scale.
The interval spacing of the notes of a scale is called a mode. The most common modes are called major and minor.
Each mode imparts a unique character to the music because of its unique combination of 1 and 2 semitone intervals from note to note.
We can hear the character of the mode because the music is written in such a way as to highlight the root note. For some examples, visit How Can We Tell Which Key We’re In?

This post is one of a growing series of free basic music theory lessons on my blog, musictheoryde-mystified.com. You can see the complete list here.

Please feel welcome to like, comment or to share this post. If you have any questions, pleased leave them as a comment and I will respond as soon as I can. If you enjoy my posts and would like to be kept up to date, please subscribe.

Much of the content is based on my upcoming music theory reference, Music Theory De-mystified, which is currently planned for release as an e-book by the end of 2023.

NEXT LESSON: 9. Accidentals, Sharpen and Flatten

PART 1 CONTENTS: Basic Music Theory Course Contents

How Can We Tell Which Key We’re In?

This post is one of a growing series of holistic investigations into various aspects of music theory. The full list can be found in the Posts page under the category Music Theory De-Mystified.

All comments are welcome. If you enjoy my post, please give it a like and share it or subscribe to my blog.

First I should say that there are two separate subjects here: the overall key and the key at a given point in the piece such as a visiting key. For the purpose of this post I’ll focus on overall key and assume a fairly simple melody but in principle, the same applies to sections and even individual phrases within the piece.

If you’re looking for a quick answer, scroll down to the summary.

When we play a scale, it’s easy to tell what the key is: it’s a combination of the root note and the mode. If we start and finish on C and play the major scale pattern of .2.2.1.2.2.2.1. (semitones), we’re in C major: C major is the major mode built on C.

But how can we hear/feel what key we’re in when the order of the notes varies, as in a melody?

If you’re reading notation, you could say, “look at the key signature”. This is true, but it’s only part of the answer. Within a key signature there are many possible tonalities. Even considering only the major and minor modes, you still need to find the right choice, to help interpret the music correctly. And if you’re listening or playing by ear, you need to be able to “feel” the key.

Look for the root note

To do this, we need to know what the root note is. For a given key signature (set of notes that make up a scale), the mode is determined by where we start the pattern i.e. the root note.

“The Spokes Of A Scale”

The best way to think of a scale is not as a strip of notes lying next to each other but as a series of spokes with the root note at the centre and the other notes around it. The double lines in the following diagram indicate the special bond between the root note and its octave (where the pattern repeats) and between the root note and the perfect 5th (more on that later in this post).

(…I see it as a kind of spiral staircase extending up and down the octaves like storeys of an apartment block, where notes on the central column are octaves of the root note…)

Root Note Power

In a piece of music, it’s as much about the relationship of each note to the root note as it is from each note to the next. To be able to feel the key we need to be able to feel the root note.

There’s a good chance that the root note is first, or at least among the first few notes, and also at or near the end, but it’s not always the case. Fortunately there are many other ways it can be pointed out in a melody.

Longest, Strongest and Most

In a melody, other than first and last, these are the three main ways we can highlight the root note.

Longest

Duration is power. Out of a series of different length notes, the longer notes are more prominent. If the root note is a long note it will stand out in the crowd.

Strongest

One way to emphasise the root note is to give it strength. There are two ways to do this:

by playing that note louder than the others or giving the note an accent (a strong attack).
by making the root note appear on the strongest parts of the bar. Time signatures have an implied hierarchy of strong and weak points- a default rhythm, if you like. Placing the root note on beat 1 gives it the most strength. In 3/4 and 4/4, beat 3 is also naturally strong. Similarly, on-beat quavers are naturally stronger than off-beat quavers.

Most

Another way to reinforce the root note is to keep coming back to it. The more often we hear it compared to surrounding notes, the more we believe it.

Examples

Here are a few single-phrase “melodies” using just a single technique to highlight the root note. For the following examples, as you listen, try to hum the note that feels like the root note. Bear in mind that no single note will fit all the time. What we’re looking for is the note that fits most of the time. When you stop listening, which single note would you remember? Try a few if you’re not sure…

The examples are all in C major, so if the techniques I have described are effective, C should feel like the root note.

To make it a fair test, I have tried to make the (mini) melodies fairly random apart from the parameter we’re testing, so they’re not great. Real composers use a combination of these techniques when creating a melody.

Longest

Strongest

Most

Lowest & Highest, Direction

Although not as significant overall, the lowest and highest notes of a passage within the melody will be naturally emphasised. I see this more as a sense of direction. When listening, we follow the direction of a scale-like series of notes, upward or downward, to its destination. The series directs us to the destination, giving that last note emphasis, before changing direction.

A scale played ascending then descending is as good an example of this as any. Scales are essentially very simple melodies with no detours.

Lowest, highest, direction

Harmonic Reinforcement

The perfect 5th, a great support act

The 5th note of a scale is almost as special as the root note itself and warrants a post of its own. I will say that it has both the capacity to blend well with the root note to support it (even if the notes are one after the other rather than played together) and to be a convenient destination for the melody to visit, a temporary root note of its own.

As a supporting note it is second to none. A 5th nearby will reinforce the presence of the root note by “pointing to it”. The 3rd note, especially the major 3rd, can also help in this way.

Some melodies place all 3 notes of the home key’s triad (chord) near each other, virtually acting as an arpeggiated chord, providing an even stronger emphasis.

Harmonic reinforcement from the perfect 5th

Accompaniment

We haven’t talked about chords yet. Chords have an enormous say in what feels like home. Chords (at least the basic types) feature the three most important notes of a key, the 1st (the root note), the 3rd and the 5th. These notes blend so well together that they reinforce the chord’s root note.

While the chord sounds (if it sounds for long enough), it’s hard not to feel that its root note is, temporarily, the root note of the piece.

The most prominent chord overall, especially towards the beginning and end of the piece, is generally that of the home key.

Other chords can also feel like home for a while if they sound for long enough, providing visiting points in the melody. This is one of the tools a composer can use to create music that has a journey, a sense of going places, rather than being stuck at home the whole time like a COVID lockdown.

The techniques described in this section are also used to establish the new key after a modulation (key change).

Even when no chords are played, the melody’s sense of direction and use of the above techniques can suggest some of these temporary keys. Chords can also be played melodically, as a series of notes called a triad. Many melodies are largely made up of scale-like passages and triads.

In A Nutshell

To answer the title question: look for the root note. The music makes sense when you can hear/feel how the other notes relate to the root note.

Look for a strong note or a strongly supported note early in the piece and towards the end. Feel the flow of the melody’s phrases- where the phrases start and end, which notes are emphasised. When a phrase is arriving home, you will hear it.

Once you know the root note, the mode will become evident, because you’ll interpret the other notes from the root note’s perspective. You can confirm this by playing the notes of the melody as a scale starting on the root note. If you have chosen the root note correctly, the tonality of the scale will match the overall tonality of the piece.

Much of the content is based on my upcoming music theory reference, Music Theory De-mystified, which is currently planned for release as an e-book by the end of 2022.

Please feel free to comment. I have a slightly unorthodox way of presenting music theory concepts but the concepts themselves are well established. If you like my posts, please subscribe so you can be informed of new posts.