AoS: Harmony and Tonality

AoS 2: Harmony and Tonality

Harmony:

Harmony occurs when two notes of different pitch are sounded together. When we think of harmony we usually mean the notes that accompany a melody. Harmony has the power to make a melody richer and more emotional.

There are many different types of harmony and harmonic devices. You will need to learn the following terms and be able to recognise them, or comment on their use in short musical extracts:

Tick below when you are happy with your understanding of these key words:
Diatonic, chromatic
Consonant, dissonant
Pedal, drone
Cadences: perfect, plagal, imperfect, interrupted, tierce de Picardie
Major, minor and dominant seventh chords using Roman Numerals or chord symbols.

Diatonic and Chromatic:

Diatonic harmony uses only notes that belong to the scale or key that the music is written in. For example a piece of music is in the key of C major, it will mainly use the notes of the Cmajor scale, ie: no sharps of flats.

Diatonic harmony will only use notes from the same scale. Chromatic harmony uses other notes as well. For example, in the key of C major any sharps or flats (the black notes on the keyboard) which are used in the harmony do not belong to the key of C major. They are chromatic notes. Chromatic means colour and these notes are used to add colour to the harmony, helping to enhance the emotional effect of the music.

Consonant and Dissonant:

When you listen to a piece of music you might think the harmony sounds nice or you might think it sounds clashy and horrible. The first nice sounding harmony is called Consonant and the second horrible type is called Dissonant.

Dissonant harmony is often used to create suspension or tension in a composition.

Pedal and Drone:

A pedal note is held on (sustained) or repeated while the harmonies change. It can be “doubled” adding the same note an octave higher or lower. The harmonies above the pedal note must change otherwise it’s not a pedal note. Pedal notes are usually in the bass part but sometimes they are higher than the melody and this is called an inverted pedal.

A drone is played n the bass. It can be just one note, like a pedal, but often has two notes played at the same time – like the drone played on a bagpipe. The two notes are usually a fifth apart, for example C and G, played in the bass, below the melody. They may be sustained or repeated. Drone are often used to accompany melodies in folk music or medieval music, particularly dance music.

Degrees of the scale:

Notes can be identified by letter names (A,B,C etc) but when they form a scale they can be identified by Roman numerals (I,II,III etc) or be special names which indicate the degree of the scale: tonic, supertonic, mediant etc See the example below for the C major scale.

The Roman numerals and names for the degrees of the scale can be used for any scale.

Cadences:

A cadence is formed by the two chords that come at the end of a musical phrase. Cadences are a kind of “musical punctuation”, like full stops or commas. There are four main kinds of cadence:

Perfect Cadence

This is made up of two chords: the dominant (chord V), which is the chord built on the fifth note of the scale. A perfect cadence is like a full stop. It gives the music a sense of completion.

Plagal Cadence

This has the subdominant chord (chord IV) followed by the tonic (chord I). It is another example of a ‘full stop’, but it is not as strong as a perfect cadence. It is sometimes called the Amen cadence as it is used to harmonise the Amen at the end of hymns.

Imperfect Cadence

This has the opposite effect. It acts as a musical comma: the music must move on after it. An imperfect cadence is made up of any chord but typically chord I, II or IV – followed by the dominant chord V.

Interrupted Cadence

This is sometimes called the ‘surprise cadence’. It is quite easy to recognise. It starts with chord V but instead of being followed by the expected tonic chord (I), it goes to the submediant chord (VI). It is another example of a musical comma; the music must move on to finish.

A chord has two or more notes of different pitch sounded together. The most common type of chord has three different notes. It is called a triad. Triads can be built on any note in a scale. The lowest note is the one that gives the chord its name; it’s called a root. Above it we add notes a 3^rd and a 5^th above the root. It is important to count the root as number 1 when working out the notes above it. We can also add in a fourth note to a triad by doubling up a note from the triad an octave higher or lower.

Chords can be named by the letter name of their root note or from their position in a scale by using Roman numerals:

Triads can be major or minor. The difference is that the middle note (the 3^rd) is a semitone lower in a minor chord than a major. In a major scale, the major chords are I, IV and V. The others are minor chords, except chord VII. This is an example of a diminished chord, which you won’t need to recognise for GCSE.

In Cmajor they are:

Major Chords Minor Chords

I = C II = Dm

IV = F III = Em

V = G VI = Am

Work out what they are in G major:

Major Chords Minor Chords

Dominant seventh chords:

To create a Dominant seventh chord we add an extra note to the triad of the dominant chord. The new note is seven notes above the root. The example below is in C major and shows chord V and V7. It’s called the Dominant seventh chord because we add a seventh to the dominant chord. It can be used as an alternative to the dominant chord.

AoS 2: Harmony and Tonality

Tonality:

Tonality means that the music belongs to a key: it is built mainly from notes of a particular scale. The strongest note in any scale is the tonic (the note the scale starts and ends on). This has the effect on the other note in the scale; in tonal music there is always the feeling that the music needs to end on the tonic. This also applies to the harmony, since chords are built on notes of the scale. Chord I is the tonic chord.

Tick below when you are happy with your understanding of these key words:
Major, minor and modal tonalities
Identification of keys up to 4 sharps and flats
Modulation to the dominant in major or minor keys or to the relative major or minor.

Major and Minor Scales:

Scales are made up of tones and semitones. In a major scale the semitones always occur between the 3^rd and the 4^th and the 7^th and 8^th notes of a scale.

Look at the keyboard below – notice that there are black notes between all the white notes except E and F, and B and C which are a semitone apart.

1 2 3 4 5 6 7 8

In a minor scale the most important difference is that the 3^rd note is lowered by a semitone.

Key Signatures and minor keys:

Because a major scale must have semitones between the 3^rd and 4^th and 7^th and 8^th notes of the scale, Cmajor is the only major scale which can be played only using the white notes of a keyboard. If we start a major scale on any other note we will have to use the black notes – sharps # and flats b to make the semitones occur in the right place. In notation instead of writing sharps or flats each time they occur, they are written at the beginning of each stave, after the clef. This is called a key signature.

Minor keys also have different key signatures, depending on their starting note. For each major key there is a minor key that shares the same key signature. In this case the minor key is called the relative minor. Relative minors are always a 3^rd lower than their relative major key. In a minor scale the 7^th note (leading note) is often raised by a semitone, but that is not part of the key signature.

The scale for C Major is shown below along with the scale for it’s relative minor A minor.

You will need to learn the key signatures up to four sharps and flats.

Modes:

Modes are ancient scales and are very distinctive. Each mode has a different structure of tones and semitones, unlike major and minor scales although they sound like a mixture of the two.

Unlike major and minor scales, where there is a semitone between the 7^th and 8^th notes of the scale, most modes have a tone between the 7^th and 8^th notes. This gives the music a distinctive sound.

Modulation:

Modulation is when the music changes key. In the examination you may have to recognise modulations from the tonic key. These will be either to the dominant (the key a 5^th above the dominant) or to the relative major or minor.