If you are trying to write music in the Western Classical Tradition (and more specifically in the style of Haydn and Mozart) you should use the common phrase structures and follow the basic conventions outlined elsewhere on this site. In addition, there are a number of common features that are found in nearly all Classical pieces and if you include them in your composition it will sound much more authentic. Some of the main WCT fingerprints are listed below, with links to explanation and examples (mostly Classical string quartets but a few others as well):
- Common cadences (using chord ii and cadential six fours)
- Circle of fifths (notes on other harmonic sequences – PDF)
- Parallel motion (3rds and 6ths)
- Octave unison
- Tonic pedal
- Dominant pedal
- Diminished seventh chord [video explainer]
(or secondary dominant) - Augmented sixth chord
Idiomatic modulations (including pivot modulations)
Extras
Some more advanced fingerprints for Romantic Chromatic Harmony (PDF)
Notes on codas: