Types Triads

Terms

Augmented Triad

A triad consisting of two stacked major 3rds. This will create the interval of an augmented 5th between the root and fifth

   M3  M3  A5    

Major Triad

A triad with a major 3rd on the bottom and a minor 3rd on the top. This will create the interval of a perfect 5th between the root and fifth. All of the notes will be notes in the major scale (major key) of the bottom note.

   M3  m3  P5   

Minor Triad

A triad with a minor 3rd on the bottom and a major 3rd on the top. This will create the interval of a perfect 5th between the root and fifth.

   m3  M3  P5    

Diminished Triad

A triad consisting of two stacked minor 3rds. This will create the interval of a diminished 5th between the root and fifth

   m3  m3  d5     

Notice how each triad gets progressively smaller starting with the augmented triad and going down to the diminished triad.

The major triad lowers the fifth of the augmented triad.
The minor triad lowers the third of the major triad.
The diminished triad lowers the fifth of the minor triad.

Another way to think of the triad types is to compare each one to the major triad.

The augmented triad raises the fifth of the major triad.
The minor triad lowers the third of the major triad.
The diminished triad lowers the third and fifth of the major triad.

For more review on triad terms and the major triad see Understanding Triads.

For a review of thirds see Major Intervals.

Building Triads

Building an Augmented Triad

There are two ways to build an Augmented Triad: by intervals or by adjusting a major triad. The simplest way to build an augmented triad is to build a major triad and raise the fifth. In a previous lesson you learned how to build a major triad, so we will assume you already know how to do that. Below are the steps to building an E♭ Augmented Triad.

Build an E♭ Major Triad

      

Raise the fifth ½ step by addding an accidental. Do not change the note - only change the accidental or add one if necessary. To raise the B♭ ½ step we will remove the flat to make the note a B natural.

     

We now have built an E♭ Augmented Triad.

Building A Minor Triad

The simplest way to build a minor triad is to build a major triad and lower the third. Below are the steps to build an E♭ Minor Triad.

Build an E♭ Major Triad

      

Lower the third by ½ step. We can do this by adding a flat to the G.

       

We have now built an E♭ Minor Triad.

Building A Diminished Triad

The simplest way to build a diminished triad is to build a major triad and lower the third and fifth. Below are the steps to build an E♭ Diminished Triad.

Build an E♭ Major Triad

      

Lower the third and Fifth by ½ step. We can do this by adding a flat to the G and changing the B♭ to a double-flat.

       

We have now built an E♭ Diminished Triad.

How to Identify Triads

There are three ways to identify triads:

Identify the quality of each of the stacked thirds that make up the triad.
Use the major key signature of the bottom note to see if all the notes are part of the key signature. If they are, then it is a major triad. If not, notice what notes are altered.
- If the fifth is raised by ½ step it is Augmented
- If the third is lowered by ½ step it is Minor
- If the third and fifth are lowered by ½ step it is Diminished
- For a review of major key signatures see Major Key Signatures.
Memorize the triads that are common in each key. We will work on learning these triads in a later lesson