Counterpoint Study 1: Interval

Counterpoint Study Lesson 1: Interval

Counterpoint is one of the fundamentals in musical composition. It is very important in composing structured music. Counterpoint was widely used and developed in Baroque era. One of the pioneers in counterpoint music was Johann Sebastian Bach. Counterpoint music can be identified by its complex-structured polyphony. In Baroque music, counterpoint can be found in many forms, such as fugue, sarabande, gavotte, minuet, gigue, even in toccata.

I've been interested in studying everything related to musical composition. Recently, I joined an online class held by IMI (Indrapraja Music Institute), taught by its founder (and also my friend) Mr. Diecky K. Indrapraja himself, to increase my knowledge in composition. This online counterpoint class is very interesting. I study along with two other students who are currently studying music in various universities. This page, and other next pages titled "Counterpoint Study", will be my notes while studying this particular subject.

The word "counterpoint" originates from Latin words, contra punctus. In musical terms, these words mean point against point. A point here is associated with a musical note. Therefore, counterpoint generally discusses how to create a note which counters another note.

Because counterpoint discusses about relations between notes, one particular subject in musical theory must be understand before our study going further. The particular subject is interval. Interval measures the differences between two notes. To understand intervals, I will give a simple example. The most simple scale which can be played on a piano is C major scale. As we know, C major scale consists of 7 notes (8 notes if includes C'), which are C, D, E, F, G, A, and B (and C'). The relations among these notes form intervals. Basic intervals in C major scale is shown below.

The table above shows intervals in C major scale. As you can see, it is very simple. You can easily identify these basic intervals by using only white keys on a piano. I say 'basic' because the table above only shows intervals which are formed by white keys. What about the intervals of black keys in C major scale? For instance, what is the interval between C and E♭? To answer this, see the table below, which shows more general intervals in C major scale. 

By referring to the table above, the answer of previous question is minor third (m3). There are several terms in interval which are common in music theory. Those are: 

1. Consonant: intervals which are categorized as consonant is third and sixth. These intervals can be identified by their sound characteristics: stable, pleasant, good to hear. Hence, because of the characteristic of unison and octave, these intervals are also categorized as consonant.
2. Dissonant: second and seventh are dissonant intervals because of their characteristic: unstable, tend to change.
3. Perfect: fourth and fifth are clearly perfect intervals
4. Tritone: tritone intervals are characterized by their 'unpleasant' sound, which is very unstable. This is caused by three adjacent whole tones.

To understand more about interval, on the picture below, I've made several examples of intervals in different scales. 

Here is my analysis of the exercise: on the first bar, the first note (bottom note) is G. The first note to the second note (upper note) forms a fifth interval. But, since the D got a sharp signature, the fifth interval is augmented. Hence, augmented fifth (A5). On the second bar, the first note (E♭) forms a seventh interval with the second note (D). But, since the D got a flat signature, the interval becomes minor seventh (m7). On the next bar, the note B forms a sixth interval with G. But, what type of sixth? On a B major scale, major sixth is formed between B and G♯. Because G♭ is 2 semitones lower than G♯, the interval on the third bar is diminished sixth (d6). Next, the first note on the last bar is A♭. A♭ to C forms a major third. Since the C got a sharp signature, the interval becomes augmented third (A3). 

The next lesson is about motion in counterpoint. If anyone has any question about this interval lesson, please put your question on comment.