We all know how to play chords, it’s pretty much the first thing we learn how to do on a guitar, but as you improve and learn more weird and wonderful chords it’s very useful to understand how they’re made, where they come from and the relationships between the notes in any given chord. A knowledge of this (even just a basic knowledge) allows you to create your own chords, work out what they are and how to find melody notes that fit with them.
In this post we’re going to be dealing with basic triads, or simple three note chords, the simplest of which can be created by using the notes from a major scale (see a post on the major scale here, and if you haven’t read it yet, then you really should do so before going any further!). Let’s use the C major scale to start with.
C D E F G A B C
To make a chord we’re going to use the first, third and fifth notes of the scale, so C, E and G. The first note is called the ‘root note’ of the chord, the others are called the ‘third’, and the ‘fifth’ because of their relative positions in the scale. These terms are known as ‘intervals’ – gaps between notes, and understanding these becomes more important as we go on. If we play these notes on a guitar we get a happy sounding chord which looks like this:
Although it doesn’t sound particularly good like that, so on a guitar we duplicate some of the notes to spread the chord across more than 3 strings, and end up with what we know as a conventional C chord:
The notes in this version are CEGCE, and the intervals are R35R3. Just three notes, a simple major triad.
If we follow exactly the same process but start from D instead, and treat it as the root note, we can use the notes D, F and A to make a chord. If we play these on the guitar we get a sad sounding chord which looks like this:
But is more conventionally played like this:
Which is the Dm chord we all know. The notes and intervals are in a different order this time – DADF – R5R3. This shows that it doesn’t matter which order we play the notes, so long as the 3 required notes for the chord are present it will always be the same chord regardless of where and how it is played. To clarify, if you play D, F and A at the same time it will always be a Dm chord, which is why you can play the same chord in a variety of different places. Each different version is called a voicing.
So if we follow exactly the same process from each note of our C major scale we end up with a specific sequence of chords like this:
C Dm Em F G Am Bdim C
What’s really cool about this is that if we pick another scale, say G major, and do the same thing to make a bunch of chords we end up with this sequence of chords:
G Am Bm C D Em F#dim G
Different note names of course, but the same chord types in the same places. Chords 1, 4 and 5 are always major, chords 2, 3 and 6 are always minor, and chord 7 is always diminished. Because we used the same formula to create the scale in the first place, the relationships between the notes haven’t changed, therefore the chord types produced will be the same.
A group of chords like this are said to belong to a ‘key’, so above we have chords from the keys of C major and G major. No two keys will have exactly the same chords because no two keys have exactly the same notes, so from knowing all of this stuff we can work out what key a song is in (note – not all songs are exclusively in one key, or solely use the chords from just one key. All sorts of borrowing and swapping around goes on, but we’re going to totally ignore all of that for now).
Let’s say Pop Song 1 has a verse that goes like this:
C | G | F | G
Or these days it’s more likely to go like this:
C | G | Am |F
Either way, a quick glance at our two sequences of chords above will show us that all the chords feature in the C major one, so this section of the song is in the key of C major.
Pop Song 2 goes like this:
G | D | Em | C
Which tells us that this song is in the key of G major. .Of course it’s not always this obvious, but you get the idea. So, learn your major scales people – if you know them then you’ll know all the basic chords that you can use in any key. And all of this stuff is really useful from creative and practical standpoints, but we’ll come on to that another day.
Happy playing!