5 – Western Music Systems – How scales are used to compose music (Melody and Harmony)
The first dimension of music is the melody or the tune. Melody is a pleasingly ordered set of notes chosen from the scale. The notes are strung together so as to create tension and then to release the tension created. Tension and release are also created by the way the notes ascend and descend. The way the notes are ordered also induce consonance and dissonance between the notes.
Melodies usually start out on a note called the tonic (the root note of the scale. For example, C of C major or the G of G major scales are the root notes or tonics). The root is in consonance with the third note and the fifth note of the major scale (major third and perfect fifth) but is in dissonance with the note that is a semitone lower than the fifth (diminished fifth or tritone). For example, C is in consonance with E and G but in dissonance with F#. Consonance produces a pleasing effect, while dissonance produces a disturbed or sad emotion. C and E or C and G sounded one after the other sounds good, but C and F# one after the other produces a very dissonant (an almost evil) effect. Try these two combinations on a keyboard or a guitar and see the effect for yourself. (The title theme of the ‘The Simpsons’ has this eerie feeling because it uses the tritone).
[The main reason why a major third (four semitone interval) produces a happy feeling but a minor third (three semitone interval) produces a sad feeling, has to do with the harmonics produced when you sound a note. These harmonics run at double, triple, four times etc. of the main frequency of the sound. Though the harmonics are not very loud, they are still there in the background. So, when you sound the note C4, the next harmonic is C5, then G5, then C6, then E6 etc. When you play the next note after C, the note combines without interference with the harmonics and hence you get a pleasing sound. Some of the other notes interfere with the harmonics and create a displeasing sound.]. The third note in a major scale (four intervals away) thus is consonant with the root, while the third note of the minor scale is in dissonance. This is why a major scale sounds happy while a minor scale sounds sad.
Consonance and dissonance also play a great part in harmony. Chords of music (triads) which are three notes played together have the function of creating these moods. A major chord has the root, the major third and the perfect fifth sounded together (that is, for example, C, E and G). A minor chord on the other had has the root, the minor third and the perfect fifth sounded together (C minor chord, for example, has C, E♭ and G).
Different instruments (including the voice) played together or individually try to create these pleasing effects using melody and harmony. Harmony along with melody are the two key elements of a piece of music.
The other important thing in melody is creating tension and releasing it. The melody starts, as we said before, on the root note and when the dominant note (the perfect fifth on a major scale) is played, it builds a tension that wants to resolve by going back to the root. Similarly, the note that is one semitone lower than the root note, the seventh note of the major scale (note B in the C major chord) also creates an intense longing to resolve to the root note. Using such combinations musicians create tension and release which is the essence of music.
Melodies are created by stringing together notes in a pleasing way. Each of these notes have different duration of sounding (or singing) and different levels of loudness. Small phrases or riffs that create a pleasing effect are first created and these are then combined together, in a repeated fashion, with different developments and changes on them. These phrases themselves may be formed by shorter pieces called motifs (these phrases and motifs are what stays in your mind for a long time after you have heard a song. The opening 4 notes of Beethoven’s fifth symphony is a famous example: G G G E♭. Then, the same four notes repeated one note lower F F F D. The second note in bold of the two four note motifs are emphasised. The fourth notes in the two motifs are elongated. Listen to the first movement of Beethoven’s fifth here.) These phrases together form what is called a long section of music called the theme.