I have recently had a big eye opener with one of my guitar pieces in how it uses dissonance in a musical way to make interesting music. I have always thought that for music to be dissonant is for it to be poor or bad but it seems to me like dissonance can be used like a theme for music.
What is the proper understanding of the use of dissonance in composition?
"it seems to me like dissonance can be used like a theme for music."
What is the proper understanding of the use of dissonance in composition?
First off, dissonance is the general term for a clash or tension in a single chord or sound, such as one might have playing a half step (minor second) or a tritone (diminished 5th, augmented 4th). Consonance, its opposite, also applies to a single moment in time, and is the general term for a resolved chord like the octave or (opinions vary) the fifth.
The idea of a proper understanding is inherently subjective. As the commenters have pointed out, the question of what dissonance is in general not only doesn't but shouldn't really have a definite answer. It "probably requires a vast historical review" and "varies wildly between different schools and genres." Note that, although the octave is present in music internationally, it is hard to argue the same about other intervals and chords. Dissonance is often what is seldom heard, while consonance is what is natural to the culture, and then there is always the octave.
But, that is not the question you asked: you want to know about dissonance as a theme in music. So the question is interpreted to not be about dissonance internationally, but about dissonance in context.
Every chord is composed of three or sometimes more notes, but one should observe that no matter what chords are heard there is always a way to interpret the chord in the scale. Say I am playing in C major. Western Music Theory notes that the "Tonic" Chord on C is the resolving chord, and the "Subdominant" F leads into the "Dominant" G. So chord progressions like "C, F, G, C" are interpreted as natural paths from the tonic, to the subdominant, to the dominant, resolving to the tonic again.
Dissonance as a theme relies on playing a scale in other ways than the Western musical standard of consonance. Although improper by more strict standards, this allows dissonance to be a theme.
The trick of the theme of dissonance is that you cannot resolve simply, as in going from the dominant to the tonic, in whatever key. Moving from the dominant to the tonic by taking a long complicated chord progression to resolve will give a buffer distance of dissonance before an unexpected partial resolution, which is one difficult way to achieve a dissonant theme. Repeating that same pattern so that it becomes more natural will still give the piece some cohesive nature. One easier way would be to use seventh chords or some jazzier varieties to make the resolution less complete: the tonic is reacher from the dominant, but neither have their way.
Remember that if you play any chord too much, the ear will hear that as the new Tonic and an aural key change will take effect: you will end up resolving unintentionally to a different key.
So dissonance as a theme requires an adept understanding of purposely defying the structure of the key, while introducing an unnatural structure that won't be a complete lack of musical coherence.
As a qualifier, it is generally easier and more praised to play music in Western culture the way the Western standards are set, although that was not your question.
A dissonance is a point of harmonic (vertical) tension in a moment of music, mostly caused by the clashes of each notes overtones in the chord that's heard at that moment.
If you were to play a C and a G above that C at the same time, that would sound relatively "consonant" because the distance from C up to G falls within the harmonic overtones for the C note, and the overtones for each note have a significant amount of overlap.
If you were to then play the B just below the C while playing the F just below the G, that would create a dissonance because the overtones for the B and F essentially clash. Move back to the C+G combination, and you've created a "consonance-dissonance-consonance" ABA structure.
If we put aside rhythm for this discussion, the ebb and flow of a piece is often tied to the amount of dissonance in the sequence of chords in the tune.
A simple answer:
Dissonance is resolved by consonance. In other words, dissonance tends toward, or leads to, consonance. The way you get there is more interesting than where you are when you get there.
https://wmich.edu/musicgradexamprep/NonChordTones.pdf
I think that 3 sources can help to clear up this question, that is H Helmholz, J.Rameau and fake-books in which you ought to analyze only acknowledged works. H. Helmholtz explained dissonances by interaction of chord's partials with near frequencies. Long before Helmholtz didn't dispose by this explanation and derived his recommendations from study of music works. These recommendations are cited in the article "J.P.Rameau on properties of harmonies".
I will try to restate what Rameau had in narrative form said:
Rameau didn't gave recommendations in what cases strong dissonances are permitted to be used. This question may be cleared up thank to fake books. By it you ought to remember that according to Rameau they arise from seventh chords, then You should see that they are used in cadences.
