Dave Clews on dissonance and consonance
Like most art forms, music is all about light and shade – to get the best result, you have to have a blend of both. In this regard, two of the main things to consider when composing a piece of music are consonance and dissonance. It’s all to do with the intervals between note pitches. If we take two notes and count the number of semitones between their pitches, the result is known as an interval, and each different interval can be labelled either consonant or dissonant.
The dictionary definition of consonance is ‘harmony and agreement among components’, so consonant intervals are usually pleasant to listen to, fostering a sense of agreeable wellbeing and satisfaction. In short, they just sound nice. A dissonant interval, however, just generally makes you wince, and the tension it creates just makes you want to hear a consonant interval as soon as possible after it – a concept that’s known in music theory circles as resolution.
Dissonance can be used to great effect in composition to evoke emotion. Pretty much the whole spectrum – from wistful sadness and poignancy through to outright fear and terror ( Psycho shower scene anyone?) – can be transmitted through artful use of it.
This month, then, I’ll delve into which intervals qualify as consonant or dissonant, and show a couple of ways in which you can exploit the contrast between the two, to add a touch of sophistication to the music you create.