Chordal Structure: Building Triads By Intervals

by KicknGuitar (Dec 23, 2007)

Chordal Structure: Building Chords By Intervals

If you do not understand intervals or just gotten rusty, you will want to read, The Many Faces of Intervals: An Interval Intro to Quality and Size
You can build any chord as long as you know the Major scale. No no, I am not lying. In this lesson, I will show you how to build chords from their titles.

You will run into more and more chord names. The first and most basic is the triad.

Triads
Triads are three note chords.
These are built in a few fashions,

Major Triads
These contain a P1, a M3 and a P5 from the Major scale.
For example, to make a C Major Triad we take the P1 from the C Major scale, a M3 and a P5. See chord chat for each interval's position.

C Major
E A D G B E
-–––––5–-–-
| | | | | |
| | 3 | | |
| 1 |•| | |
| | | | | |
| | |•| | |


Minor Triads
These contain a P1, a m3 and a P5 from the Major scale.
For example, to make a C Minor Triad we take the P1 from the C Major scale, a m3 and a P5. See chord chat for each interval's position.

C minor
E A D G B E
-–––––5–-–-
| | 3 | | |
| | | | | |
| 1 |•| | |
| | | | | |
| | |•| | |


Augmented Triads
Augmented triads contain a P1, a M3 and a Aug5.
For example, to make a C Augmented triad we take the P1 from the C Major scale, a M3 and a Aug5. See chord chat for each interval's position.

C Augmented
E A D G B E
-–––––-–-–-
| | | 5 | |
| | 3 | | |
| 1 |•| | |
| | | | | |
| | |•| | |


Diminished Triads
Lastly, diminished triads contain a P1, m3 and a dim5.
For example, to make a C diminished triad we take the P1 from the C Major scale, a m3 and a dim5. See chord chart for each interval's position.

C diminished
E A D G B E
-–––––-–-–-
| | | | | |
| | | | | |
| 1 |•| | |
| | 5 | 3 |
| | |•| | |


These are just the bare wire structures of triads. You can add more notes or less to change the sound of them. Their positions can change to. Try using the the Major scale to figure out this chord (start on the low F):

E A D G B E 
-–––––––-–-
O | | O O O
| | | | | |
| O O•| | |
| | | | | |
| | |•| | |

Use this F Maj. chart if you need help.
E A D G B E 
7–3–6–2–5–7
1 4 | | | 1
| | 7 3 6 |
2 5 1•4 | 2
| | | | | |
| | |•| | |


Figured out the intervals in the chord? We used F Major because F was the lowest note from the chord. Check your results with the following chart.

E A D G B E 
-–––––––-–-
1 | | 3 5 1
| | | | | |
| 5 1•| | |
| | | | | |
| | |•| | |
Intervals as they appear in the chord: P1, P5, P1, m3, P5, P1.

In this F chord we find a P1, a m3 and P5, exactly what a minor chord is made up of.

Be cautious of using the Major scale with a preexisting chord. Not all chords have the tonic as the lowest note (notes other than the tonic as the lowest are known as Inversions). This is a good way to dissect a chord you already know the name to.

Key
E A D G B E 
-–––––––-–-
| | | | | |< First fret, unless specified
| | | | | |
| | |•| | |< Third fret
| | | | | |
| | |•| | |< Fifth fret


1 - Any type of a first interval
2 - Any type of a second interval
3 - Any type of a third interval
4 - Any type of a fourth interval
5 - Any type of a fifth interval
6 - Any type of a sixth interval
7 - Any type of a seventh interval

Hopefully the confusion isn't as hazy as before. Feel free to question, comment and Kvetch.