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An Introduction to MusicTheory

Part One

Introduction

The purpose of this lesson is to explain the basic elements of "practical" music theory so that applications such as chord formation, soloing and transcribing skills can be developed. This introduction should enable you to progress further by seeking professional tuition if desired. Such tuition will help you develop other aspects that are not considered here, such as correcting bad habits and helping you to create your own style and this will proceed at your own pace.

Music theory is one big subject to learn. There is a seemingly overwhelming amount of information to take in and because of this I have written the lesson in three parts. It is heavy going at first (this first part is the worst!) but stick with it and feel free to mail me any questions (Andrew@lyonap.force9.co.uk).

This first part of the lesson deals with the major scale system, the second part will deal with chord formation, intervals and modes and the third part will deal with soloing.

Throughout the lesson capital letters are used to represent major chords i.e. C F G and a lower case "m" represents minor chords i.e. Dm Em.

The Major Scale System

The vast majority of music in the West is based on the Major Scale system. This was devised by Pythagorus and consists of the following twelve chromatic (semi-tone or one fret increment) scale degrees - C C#/Db D D#/Eb E F F#/Gb G G#/Ab A A#/Bb B C If you are familiar with a piano or keyboard, the 5 black keys are the sharp/flat notes indicated above. Incidentally, I have not yet found an explanation for why there is not an E#/Fb nor a B#/Cb note. For now I am notating using both the sharp and flat notation where applicable - this will be discussed further under "Cycle of Fifths".

Each of these 12 chromatic scale degrees forms the root of a major scale. Each major scale is formed with a fixed series of intervals from the "key" note on which it is based and these intervals are exactly the same for each of the twelve major scales. Conventionally, we use the expression "key" to describe which major scale any particular song is written in. However, being fairly lazy creatures instead of saying "written in the key of C major" it is more usual to say "key of C".

The intervals for a major scale are; tone, tone, semitone, tone, tone, tone, semitone. (T T S T T T S)

We now have seven scale degrees within a major scale, each of which has a name that denotes its relationship to the first note, or tonic. As well as playing each note as an individual tone of the scale, it can also form the root note of a chord. There is also a fixed pattern to describe the nature of each chord (i.e major, minor or diminished) and again this pattern is exactly the same for each of the twelve major scales.

We shall consider the key of C, as this has no sharps or flats. This is shown below:

From the above it can be seen that starting at C, we move up a tone to D, a tone to E, a semitone to F, a tone to G, a tone to A, a tone to B and a semitone back to C (an octave higher than the starting note). Also, you will sometimes find that scale degrees are notated using roman numerals - again there is no right or wrong way.

Incidentally, I find that names of each position are seldom referred to. The most commonly used are the first position - tonic; the fourth position - sub-dominant; the fifth position - dominant and the sixth position - relative minor. I find it more useful to think in terms of the intervals between notes rather than relative positions i.e. an interval of a fourth is shown as C to F above and an interval of a fifth is shown as C to G above. Intervals will be considered in more detail in part two.

Cycle of Fifths

Now that we are familiar with the key of C, we can start to consider the other 11 keys. The twelve keys are listed chromatically above, but this doesn't help to explain the link between them musically. If you imagine that the keys are the hours on a clock face, following the cycle of fifths will bring you back to the original starting point. Because it is a circular process, you can start with any key and progress through the full cycle through all the other eleven keys back to the original key that you started from. It is conventional (and easiest) to start with the key of C as there are no sharps or flats contained within it. The cycle progresses as follows;

1. For ease of reference, write the scale degree numbers then write the key of C underneath.

2. Take the fifth note as the new starting note and write it underneath.

3. Sharpen the fourth note and write it in underneath the seventh scale degree.

4. Write in the rest of the notes from the preceding key using the sequence of 6, 7, 8, 2, 3.

As a double check, the principal of T T S T T T S will always apply, and the seventh scale degree will always be a semi-tone flatter than the starting note. It is good practice to write out all twelve keys using the cycle of fifths, as this will help familiarize you with all the 12 keys and the chords contained in them. The cycle is written out in full below.

Moving through the cycle from C, it can be seen that we increase the number of sharps successively until we reach 5 in the keys of B, F# and C# and then the number decreases again.

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Cycle of Fourths

In the example above, we used a clock face as an example of the circular nature of the keys. If we consider that the cycle of fifths moves us clockwise, then the cycle of fourths can be considered to move us anti-clockwise. The cycle progresses as follows;

1. For ease of reference, write the scale degree numbers then write the key of C underneath.

2. Take the fourth note as the new starting note and write it underneath.

3. Flatten the seventh note and write it in underneath the fourth scale degree.

4. Write in the rest of the notes from the preceding key using the sequence of 5, 6, 8, 2, 3.

It is also good practice to write out all twelve keys using the cycle of fourths for the same reasons as given above. The cycle is written out in full below.

Is it # or b i.e. G# or Ab?

We can see when we compare the two cycles above that the meaning is exactly the same whether we use a G# or Ab note. Convention normally uses sharps for the keys of G, D, A, E and B and flats for the keys of Gb, Db, Ab, Eb Bb and F. However, if you find it easier to think in terms of all flat notes or all sharp notes then that's fine - there is no right or wrong way.

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I Can't Remember All That!

As I said at the start, this part of the lesson is definitely the worst! I would say though that it is not essential to know all twelve keys, as most songs will be written in the keys of C, G, D, A, E, Bb or F. It is easiest to learn one key at at a time and which chords are major and which are minor. Learning the cycles and the keys will enable you to transcribe songs quicker and more accurately - i.e. For a "straightforward" song (i.e. one key and no chord substitutions) there are only seven chords to choose from, and if the song has an Am in it, for instance, there are only three keys to choose from (C, F or G). It will also help with chord formation and soloing.

Speaking of which, the next lesson discusses intervals, chord formation and modes - see you next time!

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If you have any comments or suggestions, feel free to mail me: (Andrew@lyonap.force9.co.uk)
Andrew http://www.lyonap.force9.co.uk