Grade Six Music Theory General Knowledge, Lesson 6a. - Naming Chords

In the ABRSM grade six music theory exam, you will probably be asked to identify a chord or two. This might be in a piano score, or it could be part of a larger ensemble, in which case the notes you need to focus on are usually pinpointed for you.

You’ll be asked to identify the chord by name, state its position, say whether it is major, minor, augmented or diminished, and you may also have to name the prevailing key (see Lesson 5 on Key).

Don’t forget to double check the key signature and clef of any instruments used in the chord. If one of the instruments is a transposing instrument, you’ll need to work out what note is actually sounding at concert pitch.

In this section of the exam, you might come across seventh chords. We will discuss these in a moment. First though, let’s revise the basics of chords.

Chord Names

Chords can be named in three basic ways.

1. By letter name, e.g. “C major”.

• The four types of chord built from basic triads are major, minor, augmented and diminished.

2. By Roman numeral e.g. I or i.

• In order to use the Roman numeral system, you need to know what the prevailing key of the music is. The prevailing key is the key at that point in the music, and not necessarily the key that the piece is "in" overall.
• Capital letters are used for major chords, and lower case letters for minor chords. 
• Augmented chords are written in capital letters with the symbol + (e.g. III+) and diminished chords are written in lower case with the symbol ° (e.g. vii°).

3. By technical name e.g. “dominant” or “diminished supertonic”. The technical names of the degrees of the scale are:

• Tonic (1st)
• Supertonic (2nd)
• Mediant (3rd)
• Subdominant (4th)
• Dominant (5th)
• Submediant (6th)
• Leading note (7th)

Again, you need to know the prevailing key of the music in order to use this system.

Major, Minor, Diminished, Augmented and Seventh Chords

Chords with Three Notes

Chords which have three different notes in them can be major, minor, augmented or diminished. 

To find out what type of chord you’ve got, put the notes together as closely as you can – you should have three notes which are a third apart – a triad.

For example, this score has a chord built with four notes, but only three of them are different:

The cello has C#, the viola has A, the second violin has E, and the first violin has A. This means we have three notes: C#, A and E.  If we stack them in thirds, they look like this:

The bottom note is the chord’s name – this is a chord of A.

Next, calculate the exact interval between the lowest and middle, and then middle and top notes. Each will be either a major third (4 semitones/half steps) or a minor third (3 semitones/half steps).

For example, A-C# is a major third. C# to E is a minor third. The pattern major+minor means the chord is a major chord. There are four possible patterns of triads:

• Major+minor=major chord
• Minor+major=minor chord
• Major+major=augmented chord
• Minor+minor=diminished chord

Augmented and diminished chords get their names from the interval made between the root and the 5th of the triad. 

Here are some examples.

G-B-D# is an augmented triad, because G-D# is an augmented 5th. Similarly, G-Bb-Db is a diminished triad, because G-Db is a diminished 5th.

Chords with Four Notes

If there are four different notes in the chord, it will be* a triad plus the seventh – the note which is an interval of a minor seventh above the root (the root is the lowest note).

*Note: this is only true in the grade 6 exam. There are lots of other four-note chords, but in the grade 6 exam you are only tested on 7th chords.

In the grade six music theory exam, seventh chords are restricted to the dominant seventh and the supertonic seventh (in major and minor keys).

• In chord 1, the key is C major. The dominant chord in C (chord V) is G major. The note which is a minor seventh above G is F. So, G major plus F is the dominant 7th of C major.
• In chord 3, the key is A minor. The dominant is E major, and D is a minor 7th above E. So E major plus D is the dominant 7th of A minor.

Notice that dominant 7th chords are always built on a major triad, even when in a minor key. This is because the leading note is raised.

Inversions

All chords can be inverted. Three-note chords have three possible positions: 

• Root position (or "a")
• First inversion ("b")
• Second inversion ("c")

Look at the lowest note of the triad. This is the bass note.

If there are several instruments playing the chord, you’ll need to look carefully to see which one has the lowest note - don't forget about instruments which sound an octave lower than written, such as the double bass and bass clarinet, and watch out for transposing instruments.

Find out whether the bass note is the root, third or fifth of the chord.

• The root is the fundamental note of the triad. Root in bass = root position "a"
• The third is a third higher than the root. Third in bass = first inversion "b"
• The fifth is a fifth higher than the root. Fifth in bass = second inversion "c"

Chords with four notes have four possible inversions:

• Root in bass =  root position ("a")
• Third in bass = first inversion ("b")
• Fifth in bass = second inversion ("c")
• Seventh in bass = third inversion ("d")