Fundamentals of Music Theory

Fundamentals of Music Theory

Learning the basic fundamentals of music theory can make a huge difference to your understanding of music, and how to play your instrument. Music theory isn't just for the professionals. It also isn't just about learning to read and write musical notation, although we cover that too. Anyone who wants to improve their playing, or become a better composer of music, can benefit so much just by grasping some of the basic concepts. Sure, you can study at college, university or a conservatory if you wish to take it to the next level, but everyone has to start somewhere.

So, here we are with a series of articles to give you just that knowledge. Everything from intervals and scales to melody and harmony. Enough to set you on your way to a more enlightened understanding of music, composition and get the most from your chosen instrument. If you are just returning after digesting some of the course, or you already have some knowledge of music theory, use the navigation below to jump right in to wherever you want.

What is a Note?

A note is an audio frequency or pitch that has been given a name. In modern Western music, there are twelve such notes:

A, A♯/B, B, C, C♯/D, D, D♯/E, E, F, F♯/G, G, G♯/A

This collection of notes is known as the Chromatic scale which is essentially made up of seven letters (A to G) with a sharp ♯ / flat variation between each one, with the exception of B to C and E to F. You can think of the natural notes, those without a sharp or flat, as the white keys on a piano keyboard. The black keys are the sharps/flats.

The distance between two adjacent notes is commonly known as a semitone and is often abbreviated to just S in scale interval patterns. It is also sometimes referred to as a half tone or a half step. So A to A♯ is a semitone, A♯ to B is also a semitone, and so on.

If we move up two notes at a time, this is known as a tone, whole tone or whole step and is often abbreviated to just T. So A to B, via A♯ on the way, is a tone. B to C♯, via C on the way (remember there is no B♯), is also a tone, and so on.

These can be added together to describe a bigger difference between notes. So from A to C, three semitones via A♯ and B on the way, can be referred to as a one and a half tone difference and abbreviated to TS (tone + semitone).

Wondering about those notes that have both sharp and flat versions? When a note has two names like this but the pitch is identical, the differently named notes are known to be enharmonically equivalent. So A♯ is the enharmonic equivalent of B, and vice versa. Generally we use the sharp name when ascending up a sequence of notes and the flat name when descending down a sequence of notes.

A, A♯, B, C, C♯, D, D♯, E, F, F♯, G, G♯

A, A G, G F, E, E D, D C, B, B

What happens when we get to the end? Well we start again from A. But before we get to that, there is something we need to address.

What's with C?

If you have already looked into music theory a little, you may have noticed that C seems to have some special significance. In musical notation, the note that sits directly between the upper (treble) staff and the lower (bass) staff is known as middle C. You may have heard that same term but referring to the first note of the middle octave (see below) in the centre of a modern piano keyboard. Indeed a piano keyboard is broken up into octaves/registry ranges each starting from C. Also In the Circle of Fifths, C sits in prime position at the top of the circle. Don't worry if you haven't heard of any of these references, we will cover all of them later.

To explain why, we need to delve into a little history of music.

Musical notation systems have existed for thousands of years as far back as Babylonia and Ancient Greece. The Greeks also had an understanding that a set of notes or mode starting with a different root note would create a different mood in the listener, some sad, some energetic, some calming, etc. Obviously pianos didn't exist then but just imagine the sound of playing only the white keys but starting out with a different root key. A different mood is created because the pattern of intervals between each note in the mode is not the same as a different mode.

Jumping forward to the 6th century, a system was devised using the latin alphabet to name the notes, starting with A to mark the then accepted lowest note. Later, the medieval church modes came about with each consisting of 7 notes starting from a different root and so with a unique pattern of intervals. For example the Dorian mode with the notes D, E, F, G, A, B, C which can be described with the pattern T, S, T, T, T, S, T. Due to the popularity of two of these modes, the Ionian mode (C, D, E, F, G, A, B) and the Aeolian mode (A, B, C, D, E, F, G) would later become known as the Major scale and the Minor scale respectively. The former of these, the Major scale, has since become the most popular scale in Western music. Because the C Major scale uses only the white keys on a piano keyboard, it has no sharps or flats, it is seen as the simplest example and is more often than not the first scale most budding musicians learn. As a result, present day music notation systems now define the starting point of an octave as the note C.

Okay, now we got that out of the way, what are these octaves we keep mentioning?

Octaves, Register and Pitch Class

Let's take the C Major scale as an example, C, D, E, F, G, A, B. If we start out with our root note of C and play through each of the other notes until we arrive at B, what comes next? Another C of course, followed again by the same sequence of notes. Now whilst these two notes are both called C and sound almost the same, the first has a lower pitch and the second a higher pitch. This is because the higher pitched C has exactly twice the frequency of the first. If we continued to the next C, that would be twice the frequency of the previous one, and so on. The distance, or interval (more on these later) between two notes with the same name is known as an octave.

Now this creates a bit of a problem. What if you are asked to play a C on your instrument of choice. How do you know which C you are meant to play? So far, when talking about notes, we have only been referring to a pitch class. The pitch class C effectively refers to all the C notes, each an octave apart from the previous C and the next C. To know exactly which C we are required to play we also need to know in which octave or registry range the C resides. Registry ranges are denoted with a number, starting from 0 for the lowest range and incrementing by one for each successive range. The number is written immediately after the note, for example C4 tells us to play the note C in the fourth registry range.

Different instruments allow different ranges and number thereof to be played. A violin might have a range from G3 to A7, a classical guitar in standard tuning might have a range from E2 to B5. A modern piano keyboard with a total of 88 keys (including both white and black keys) has a range from A0 through to C8. Remember that middle C in music notation and on the piano that we mentioned earlier? That will be C4.

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