Grade Three Music Theory - Lesson 5: Degrees of the Scale & Tonic Triads

Degrees of the Scale

The degrees of the scale are numbers given to each note of the scale in order.
The numbers are based on the ascending scale:

Tonic Triads

The first degree of the scale is also known as the tonic.

A tonic triad is a chord built up from the 1st, 3rd and 5th degrees of the scale.
For example, here is the tonic triad in F minor:

It’s built on the tonic, F, with the 3rd degree of the scale, Ab, and the 5th, C.

You might be asked to identify a tonic triad. What key is this tonic triad?

First, work out the lowest note. The lowest note here is G.

Next, look at the middle note – does it occur in the major or minor form of the scale? The middle note here is Bb. Bb occurs in G minor, but not in G major. Therefore, this chord is the tonic triad in G minor.

You might be asked to add a clef and a key signature or accidentals to a tonic triad. Which clef and key signature do we need to add to this tonic triad?

To make the lowest note an A, we need to add the treble clef. (If we put a bass clef, the lowest note would be a C.)

The key signature of Ab major has 4 flats, so we need to write in Bb, Eb, Ab and Db, in their correct positions:

It doesn’t matter which octave you write a tonic triad in. Here are two tonic triads in C major, in different octaves:

Try to avoid using lots of ledger lines though!