49. Basic Diatonic Harmony

The harmonized major scale is the source of most chord progressions in popular music. Make sure to review construction of major and minor chords before continuing. Here is a C major scale:

 

All major chords are derived from the 1st, 3rd, and 5th degrees of the major scale. All minor chords are derived from the 1st, FLAT 3rd, and 5th of the major scale. When building a chord from the 1st, 3rd and 5th degrees of the C major scale, the resulting C major chord is known as the I (one) chord, or Tonic Chord.

 

We call any chord built from the scale ‘diatonic’, which means ‘of the key’ (scale)

 

 

However, chords can be made, or “built”, starting on ANY degree of the scale. All are built in THIRDS, using the 2nd, 4th and 6th, or 3rd, 5th, and 7th and so on. IMPORTANT! Note that the term thirds means counting to 3 INCLUDING the letter you start with—E is the 3rd of C, A is the 5th of D, G is the 2nd of F, etc.

EXAMPLE:  You can make a chord starting on the 2nd degree of the C major scale by starting on D. Look at the C scale below. If you build it in 3rds, you get D, F and A:

 

 

 

If you compare that with the 1st, 3rd and 5th of the D major scale below you will see that it is a MINOR chord, because the 1st, 3rd and 5th of D is D, F# and A.

 

 

 

Likewise, if you make a chord starting on the 5th degree of the C major scale, you get G, B, and D. This chord is G major:

 

 

Note that this G major chord is made from the 5th, 7th and 2nd degrees of the C scale, since we simply start again at 8, and do not count C twice.

This chord, when made from the C major scale, is known as the V (five) chord. However, when the same chord is made from the 1st, 3rd, and 5 degrees of the G major scale, it is known as the I chord:

 

 

 

Although this is the same G major chord  in both instances, its function is different. As derived from the 5th, 7th and 2nd degrees of the C major scale, G major is known as the V chord in the key of C. As derived from the 1st, 3rd and 5th degrees of the G major scale, it is known as the I chord in the key of G.

Here is the list of  seven 3 note chords derived from the C scale, one for each degree, its chord type, and its function as a 1,3,5 or 1, b3,5 chord.

I    C        E         G                 Major          (1, 3, 5 of the C major scale)  

 

ii    D        F         A                minor          (1, b3, 5 of the D major scale)

 

iii   E        G         B                minor          (1, b3, 5 of the E major scale)

 

IV  F        A         C                Major          (1, 3, 5 of the F major scale)

 

V   G        B         D                Major          (1, 3, 5 of the G major scale)

 

vi   A        C         E                minor           (1, b3, 5 of the A major scale)

 

This chord, and its minor key, is also known as the relative minor. More on that later.

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vii   B        D         F             diminished   (1, b3, b5 of the B major scale)

     (I have put a separation line between the 6th and 7th chord—disregard the diminished chord for now.) 

Here is another example of a chord as it functions in two different keys.

Example:

 

E             G#          B                              This is the I, or tonic chord, in the key of E major

 

However…

 

E          G#          B     It is also the V chord in the key of A major

 

 

A series of chords together in a song is called a progression. If this progression is made entirely of chords in a particular key, this is called a diatonic progression. Again, diatonic means “of the key”, or derived from the key. Thus, the progression of C-Am-F-G is a diatonic progression in the key of C.

 

In theory terms, this progression is also known as I-vi-IV-V (one-six-four-five), because those are the scale degrees in C from which those four chords are built. Most popular songs are made from diatonic progressions, and many of the same ones are used over and over.  Familiarizing yourself with them gives you a much more manageable amount of information to work with when compared to the vast number of chords that exist. 

 

   I used to think if I knew all the chords I would be able to better master the guitar. I purchased several chord books with that in mind—one of them had over 1,000 chords!

 

It didn’t work for me because I didn’t know how to use them. I learned 8 different ways to play a G11 chord, but little idea of what to do with it.

Build your musical vocabulary slowly. Learning these 6 chords and how they function (again, forget the vii chord for now) is MOST beneficial. At the same time, focus your attention on the major keys of C, A G, E and D. They are by far the most common keys on guitar; the others can be easily learned later.  These 6 chords are the same in all 5 of these keys—the notes that change do so together, so there is essentially no difference. Gradually, 7th chords, suspended chords, slash chords and others can be learned, and they will make sense.

© 2012 Jim Greenfield