Interactive Crash Course in Chord Theory for Guitarists

1 Major and Minor Chords

The theory of chord construction can appear a very complex subject.  It  is not!  If you can understand the major and minor scale you can understand the most complex chord construction.  If not, Google “major scale” and “minor scale” and read as much as you need until you have a solid grip on these two concepts.  I will assume you understand these two scales for the purposes of this lesson.


Ok, let’s work in the key of C major.  Here is the C major scale, the only major scale without sharps (# symbol) or flats (b symbol).  In other words, using only the white keys on a piano.  Start on a C and move up.  The sound should be familar.

C  D  E   F  G  A  B  C

Do    re    mi     fa    so     la     ti     Do


 

Try it for yourself on this virtual piano (requires Flash installed to work!).  Click on the notes with your mouse and then try it on your guitar by following the tab below.

C  D  E  F  G  A  B  C

1)  Major Chords


To make a major chord we take the 1st, 3rd and 5th of the major scale and play them together.

So, a C major chord is made of the 3 notes

 

C (the 1st or root), E (the 3rd) and G (the 5th)


On a piano a C major chord could be played like this 

C       E      


On a guitar we can play the same 3 notes like this,using the A, D and G strings fretted as shown

                           

We can add any number of extra Cs, Es and Gs anywhere on the keyboard or fretboard to create bigger sounding C major chords, as long as the notes are only C, E and G. So another fingering for a C major chord on a piano could be

C       E       G            C       E

Which is recognisable on a guitar as the full 5 string open position C major chord

2) Minor Chords


Minor chords are also made from the 1st, 3rd and 5th notes, but from the minor scale.  Here, we will look at making an A minor chord (Am for short).  The A minor scale is the only minor scale without any black notes.


A  B  C  D  E   F  G  A  
                         
So an Am chord is made up of the 3 notes A, C and E.  Here’s one possible fingering for Am on a piano keyboard...

A       C      

And the most common fingering for an Am chord on guitar