Tonic triads are simple chords with just three notes in them.

To build a tonic triad, we start by taking the first note from any scale (which is also known as the “tonic” or “key note”).

Let’s make a tonic triad of D major.

We start by writing the first note of the scale of D major – D:  

D root of D tonic triad

Next we add a note which is 2 notes higher (also known as the third degree of the scale). In the scale of D major, the note which is 2 notes higher than D is F#:

D major tonic triad root and 3rd

Finally, we add the note which is two notes higher than the last note – otherwise known as the fifth degree of the scale. In the scale of D major, the fifth degree of the scale is A:

D major tonic triad with 5th

The notes D-F#-A make up the tonic triad in the key of D major. 

We can also build tonic triads in minor keys of course. The rules are the same, but we need to use the minor scale. In D minor, the tonic is D, the third degree of the scale is F (natural) and the fifth degree of the scale is A. So, the tonic triad of D minor looks like this:

D minor tonic triad

Tonic triads are always built on the tonic, third and fifth degrees of the scale of the same key.

Here is the tonic triad in D major, and the one in D minor. Listen to them carefully, and try to remember the difference in their sounds:

D major and D minor tonic triads

Grade 2 Tonic Triads

Here’s a list of all the tonic triads you’ll need to recognise for Grade Two , in both the treble and bass clef:

(Note: For Trinity you will not be tested on D, A, Bb or Eb major at grade 2).

grade 2 music theory tonic triads abrsm and trinity

Finding Tonic Triads in a Melody

Sometimes you might need to find three notes in a melody which form a tonic triad when they’re put together.

You’ll normally be told what key the melody is in, and could see a question like this:

This melody is in C major. In which bar can all three notes of the tonic triad be found?

find the notes that make a tonic triad in C major

Because the piece is in C major, the tonic triad must contain the notes C-E-G. (They could be in any order.)

Bar two contains the notes C, E and G, so that’s the right answer. (Bar one doesn’t contain a G, so it’s not right!)

Labelling a Tonic Triad

 We sometimes use Roman numerals to name chords. Because the tonic triad is built from the 1st degree of the scale, we chord this chord I (“chord one” – capital I in Roman numerals = 1). Minor tonic triads are sometimes written in lower case to show they are minor: i. Roman numerals are usually written below the stave.

In modern song books it’s more common to label chords by their chord symbols. The chord symbol is the letter of the root of the chord, plus “m” for minor chords. Chord symbols are usually written above the stave.

Here are some examples of tonic triads with their labels:

labelled tonic triads

Broken Chords and Arpeggios (Trinity Only)

In music, chords (or triads) can appear with all the notes sounding at the same time, or with the notes played one after another in a pattern, to make an accompaniment.

Here is an example of a chord played at the same time. It’s a tonic chord in G major. This is also known as a block chord.

block chords

When a chord is played straight up or down with one note at a time, it’s called an arpeggio. This time, each note of the E minor tonic triad is played one after another, starting and finishing on the tonic note E.

tonic triad arpeggio

Finally, a broken chord is a triad played in a pattern of three or four notes, starting on a different chord note each time.
In a pattern of three notes, the broken chord is built on the three notes of the triad. For example, here is a broken chord in A minor:

broken chord grouped in 3s

Each group of three notes contains the three notes of the tonic triad (A, C and E). Notice how each group begins on the next available note from the triad, (the first notes in each bar are A, then C, then E then A again). The three notes in each group are played in strict order – don’t jumble them around!

In a pattern of four notes, the broken chord is built from the tonic triad, plus another tonic note to “top off” the chord.

Here is a four-note pattern in E minor. This time the pattern is moving downwards. The first note in each bar is each note of triad, in order, starting from the tonic note.

tonic triad grouped in 4s

Root Position and First Inversion Triads (Trinity Only)

Up until now, all the triads we have written have been organised the same way – the lowest note of the triad is the “root” or “name note” of the chord.
Here are some examples.

tonic triads root position

The C major chord has C as its lowest note. E minor has E as its lowest note, and so on.

These are called root position triads, which means that the root (or name note of the chord) is the lowest sounding note in the chord.

For Grade 2 Trinity, you might also be asked to name or write a first inversion triad. In a first inversion triad, the lowest note in the chord is the note which is a 3rd above the root (name-note) of the chord. The actual notes of the chord are the same – it is only the order of the notes that changes.

Here are the same triads as above, but this time they are in first inversion:

tonic triads first inversion

Now, the lowest note in each chord is the note which used to be in the middle of the triad, when it was in root position. We have moved the root (name note) of the chord up one octave, and put it at the top of the chord, instead of at the bottom.

Tonic Triads Exercises

Hover your mouse over the staves to reveal the answers. (Tap on mobile devices).

A. Add the correct clef and any necessary sharp or flat signs to each of these tonic triads. Do not use a key signature.

clefs-on-triads 0 0clefs-on-triads 0 1clefs-on-triads 0 2clefs-on-triads 0 3clefs-on-triads 0 4 

clefs-on-triads-2 0 0clefs-on-triads-2 0 1clefs-on-triads-2 0 2clefs-on-triads-2 0 3clefs-on-triads-2 0 4

 

B. Name the keys of these tonic triads

tonic-triads 0 0tonic-triads 0 1tonic-triads 0 2tonic-triads 0 3tonic-triads 0 4tonic-triads 0 5 

 

C. Draw a circle round 3 notes next to each other that form the tonic triad. (The key is given.)

1. B flat major

Find the notes of the tonic triad - B flat major

2. D major

Find the notes of the tonic triad -D major

 

D. In which bar can all three notes of the tonic triad be found? (The key is given.)

1. E flat major

Find the notes of the tonic triad - E flat major

2. A major

Find the notes of the tonic triad - A major

E. Write broken chords using the tonic triad. Use the key signature. (Trinity only)

a. D minor in patterns of 3 notes, going up, finishing on A above the stave. Use quavers (8th notes)
b. E minor in patterns of 4 notes, going down, finishing on E below the stave. Use semiquavers (16th notes).

broken chord abroken chord b

 

F. Write one octave arpeggios using crotchets (quarter notes). Use the key signature. (Trinity only)

a. E minor, going up then down.             b. A minor, going down then up.         c. D minor, going up then down.

arpeggio q 0 0arpeggio q 0 1arpeggio q 0 2