Triad

Contents 1 Definition of triad 2 Basic notation 3 Types of triads 4 Symbols for triads 5 Inversions of triads 6 Other positions of triads 7 Use of triads 8 See also

Definition of triad

A triad is a special type of chord which consists of 3 different tones, in consecutive thirds.

The triad thus consists of a minimum of three intervals: 2 thirds and 1 fifth, or their respective inversions.

Basic notation

The basic notation of a triad, is by virtually taking tones 1, 3 and 5 of a scale and writing them together.

The examples below use the basic tones only and can be clicked for playback.

Basic scale and triad of c:

Basic scale and triad of d:

Basic scale and triad of e:

Basic scale and triad of f:

Basic scale and triad of g:

Basic scale and triad of a:

Basic scale and triad of b:

Types of triads

Consisting of 2 thirds and one fifth, the thirds can be major or minor, and the fifth can be perfect, diminished or augmented, there are 6 types of triads.

• Major triad: consisting of a major third, a minor third and a perfect fifth
• Minor triad: consisting of a minor third, a major third and a perfect fifth
• Augmented triad: consisting of a major third, a major third and an augmented fifth
• Diminished triad: consisting of a minor third, a minor third and a diminished fifth
• Flat 5 triad: consisting of a major third, a diminished third and a diminished fifth
• Double Diminished triad: consisting of a diminished third, a major third and a diminished fifth

These triads can occur on any tone, the examples below are the 6 triads of c (alterations are needed to obtain the tones):

Symbols for triads

For most music in which improvising plays an important role, symbols are used for triads and chords.

There is no unity in the systems used for these symbols, as different symbols occur in different books.

Below is a table summarizing the most commonly used chord-symbols for triads:

Triad		Symbols
Major	Maj	M	Δ
Minor	min	m	-
Diminished	dim	d	°
Augmented	Aug	A	+
Flat 5		♭5	-5
Double diminished		(no symbol)

Inversions of triads

A triad is still considered to be the same triad when the 3 tones it consists of are presented in another position than the basic 1-3-5 described so far. There are three basic positions for a triad:

1. The 1 is the lowest tone, this is called root position, short: root
2. The 3 is the lowest tone, this is called first inversion or sixth position, short: 6
3. The 5 is the lowest tone, this is called second inversion or six-four position, short: 6-4

The acoustic properties are different, yet these positions can be perceived as derived from one basic structure: the triad. This perception evolved by the end of the 15th century in Europe, and the triads (and their inversions) quickly entered Western classical music to dominate it for centuries to come, at the cost of the polyphony which prevailed before. Harmony thus replaced melody as the structuring principle of musical logic.

The examples below are the positions of the triads of c:

The names of the inversions are derived from the intervallic structure: the inversions of the thirds become sixths (major, minor or augmented), and the inversions of the fifths become fourths (perfect, augmented or diminished).

Other positions of triads

Any chord with more than just three tones, but consisting of just three tones making up a triad, is also perceived as, and considered to be, a triad. In this way, triads can be performed with more pitches, yet three basic tones only, as is the case in many compositions for piano, band, choir, ensemble or orchestra.

Other designations for positions of triads are:

• closed position - short CP, when no traid-tones fit between the tones played, the position of the lowest tone, the bass, is disregarded in this respect
• open position - short OP, when exactly one triad tone would fit between the tones played, the position of the lowest tone, the bass, is disregarded in this respect
• mixed position - short MP, when the position has a mix of "open" and "closed" intervals, the position of the lowest tone, the bass, is disregarded in this respect
• octave position - short 8P, when the highest tone played is the 1
• third position - short 3P, when the highest tone played is the 3
• fifth position - short 5P, when the highest tone played is the 5

Some examples, demonstrating these positions of the triad of c-major, for piano:

Use of triads

Any scale or mode can be harmonized by forming triads on its steps, these triads (or, when expanded: seventh chords) are called degrees.

The harmony thus obtained is proper to that particular scale itself and can be modal or tonal, depending on its use.

See also

• Outline of basic music theory
• Interval
• Seventh chord
• Special:Browse/Triad - browse this page to find whiteboards treating triads.