Constructing Tonic Triads

Musician playing guitar
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First, let's define each word separately; "tonic" pertains to the first note of a scale, while "triad" is defined as a chord consisting of 3 notes. Hence, a "tonic triad" means a chord of three notes, with the lowest note being the tonic (first note) of a scale. The tonic triad is always made up of the 1st (tonic) + 3rd + 5th notes of a scale. Tonic triads are built on thirds because the interval between the tonic and the middle note (3rd note of a scale) is a third; the interval between the middle note and the highest note (5th note of a scale) is also a third. Use these steps to help you form tonic triads:

First, learn how to play major and minor scales.

Major Scales:

  • C Major Scale: C-D-E-F-G-A-B-C
  • D Major Scale: D-E-F#-G-A-B-C#
  • E Major Scale: E-F#-G#-A-B-C#-D#
  • F Major Scale: F-G-A-Bb-C-D-E
  • G Major Scale: G-A-B-C-D-E-F#
  • A Major Scale: A-B-C#-D-E-F#-G#
  • B Major Scale: B-C#-D#-E-F#-G#-A#
  • C# Major Scale: C#-D#-E#-F#-G#-A#-B#
  • Eb Major Scale: Eb-F-G-Ab-Bb-C-D
  • F# Major Scale: F#-G#-A#-B-C#-D#-E#
  • Ab Major Scale: Ab-Bb-C-Db-Eb-F-G
  • Bb Major Scale: Bb-C-D-Eb-F-G-A

Natural Minor Scales:

  • C Minor Scale: C-D-Eb-F-G-Ab-Bb-C
  • D Minor Scale: D-E-F-G-A-Bb-C-D
  • E Minor Scale: E-F#-G-A-B-C-D-E
  • F Minor Scale: F-G-Ab-Bb-C-Db-Eb-F
  • G Minor Scale: G-A-Bb-C-D-Eb-F-G
  • A Minor Scale: A-B-C-D-E-F-G-A
  • B Minor Scale: B-C#-D-E-F#-G-A-B
  • C# Minor Scale: C#-D#-E-F#-G#-A-B-C#
  • Eb Minor Scale: Eb-F-Gb-Ab-Bb-Cb-Db-Eb
  • F# Minor Scale: F#-G#-A-B-C#-D-E-F#
  • Ab Minor Scale: Ab-Bb-Cb-Db-Eb-Fb-Gb-Ab
  • Bb Minor Scale: Bb-C-Db-Eb- F-Gb-Ab-Bb

Next, simplify it!

You can memorize this formula to form a major scale: whole step - whole step - half step - whole step - whole step - whole step - half step or w - w - h - w - w - w - h.

You can memorize this formula to form a minor scale: whole step - half step - whole step - whole step - half step - whole step - whole step or w - h - w - w - h - w - w.

Now, assign numbers to each note of a major or minor scale.

Always assign number one to the tonic (first) note. For example, in the C major scale the numbers will be assigned as follows:

C = 1

D = 2

E = 3

F = 4

G = 5

A = 6

B = 7

On an A minor scale the numbers will be assigned as follows:

C = 1

D = 2

Eb = 3

F = 4

G = 5

Ab = 6

Bb = 7

Remember the pattern.

Now, in order to form a tonic triad play the notes numbered 1 (tonic) + 3 + 5 of a major or minor scale. In our example above, a tonic triad in C Major is C + E + G, while a tonic triad in C minor is C + Eb + G.