Classical period - Harmony and tonality
General characteristics of harmony and tonality in the Classical period
- Tonality was diatonic - in a major or minor key.
- Diatonic chords - mainly the primary chords - were used, with occasional chromaticisms.
- Regular Two chords at the end of a phrase which indicate a pause, or ending in the music. were used to punctuate balanced classical phrases.
- The two main chords were the tonic and dominant chords - chords I and V - with some diminished seventh chords.
- Music often modulated to closely related keys.
Use of primary chords and cadences
Music from the Classical period is mainly based on the primary chords - I, IV and V, and the secondary chords - II, III, VI and VII.
Diminished chords
Question
In which key is the above chord found?
D major (C# is the seventh note of the D major scale).
A seventh is often added to a diminished chord, making it a diminished seventh. If you added a B flat to the chord above, it would be a diminished seventh. The interval between all the notes is a minor third.
Cadences
All four cadences can be found in Classical music. Perfect and plagal cadences are used to end musical phrases. Imperfect and interrupted cadences are used at the midpoint of phrases as they do not sound ‘complete’, ie the music has to move on before it resolves onto the main chord of the particular key that it is written in.
Examples
Haydn’s Symphony No. 101 in D major, ‘The Clock’, is in a major key and uses mainly diatonic chords:
A dominant seventh is used at the end of the phrase before the first time bar. This was typical of a perfect cadence in the Classical period.
Wolfgang Amadeus Mozart, Josef Haydn and Ludwig van Beethoven enjoyed giving a little more harmonic interest to their music by adding When notes from the chromatic scale are added to primarily diatonic chords and music.. Listen to the opening of Beethoven’s Piano Sonata no.8 in C minor, ‘The Pathetique’. Beethoven’s use of the A four note chord with an interval of a minor third between each note. adds drama and tension to the music.
Listen to the extract here:
Question
What kind of cadence can you hear at the end of the first phrase (0:17-0:18)?
Perfect cadence
Modulations
In the Classical period, composers used modulations to help provide contrast between key musical ideas or sections within their pieces. For example, if the first key melody was in the tonic key, the second key melody might be in the dominant key.
In common musical forms of the Classical period, such as sonata form, modulations to the dominant, subdominant and relative minor keys are all fairly common in the development section, ie the section after the exposition. The exposition is where the key ideas of the music are introduced.