Triad Quality

There are FOUR different quality of triads.  The most familiar ones are MAJOR and MINOR.  The less common ones are DIMINISHED and AUGMENTED.

Triads are made up of different combinations of major and/or minor thirds. If a triad is made up of a pair of thirds, here are only four possible combinations of these, and these are the four types of triads.

A MAJOR TRIAD is a major third between the lower two notes, and a minor third between the top two.

A MINOR TRIAD is the reverse - a minor third between the lower two notes and a major third between the top two.

A DIMINISHED TRIAD is made up of two minor thirds.

AN AUGMENTED TRIAD is made up of two major thirds.

Try writing all four triads in root position, beginning on the same root note.  This will help you understand the differences (and similarities) between the qualities of triad.  Playing them on a keyboard will help you hear the differences.

TRIADS OF THE MAJOR SCALE
In the last post, we wrote out the major scale and based a triad on each note of that scale.  The following activity can be found on the worksheet: Write one octave ascending of the major scale with TWO SHARPS in the key signature.  Then, add two more notes to each note of the scale to create a series of triads.  Label each triad using roman numerals (I, II, etc) and state the QUALITY of each triad.

It doesn't matter which major scale you do this with, the series of triads will always be the same quality:
I - Major, II - minor, III - minor, IV - Major, V - Major, VI - minor, VII - diminished, VIII [=I] - Major

TRIADS OF THE MINOR SCALE
You can do the same with the minor scale.  The worksheet activity is: Write one octave ascending of the minor scale which commences on the same key note as the example above.  Create a series of triads as before, label each triad using roman numerals (I, II, etc) and state the QUALITY of each triad.  Remember the raised seventh! (HINT: you will need to write it more than once, won’t you!?)

It doesn't matter which minor scale you do this with, the series of triads will always be the same quality:
I - minor, II - diminished, III - Augmented, IV - minor, V - Major, VI - Major, VII - diminished, VIII [=I] - minor

Here is the worksheet for this topic:

https://docs.google.com/file/d/0B9JdpU-tw7FuLWh3ZXEyZXJXeEE/edit?usp=sharing