Music Theory 101: An Easy Guide to Understanding Intervals
Keep reading to learn about intervals and test your knowledge with our interval study quiz.
In music theory, an interval refers to the pitch distance between two notes. It is determined by counting the number of letter names and the distance in pitch classes and can be classified by their distance and quality, which plays a fundamental role in harmony, melody, and chord construction.
Still confused? Okay let’s break it down further.
1. Intervals are the distance between 2 notes.
2. The interval number is determined by the distance of the musical letters. Just remember to include both the starting and ending notes when counting.
For example, the notes C to G have an interval of 5 because they are 5 letters apart from each other. The notes G to A have an interval of 2. The notes G to the very same G (a repeated note) will have an interval of 1.
3. There are 2 types of intervals: Melodic and Harmonic intervals.
A melodic interval is when 2 notes are played one after the other, like in a melody. A harmonic interval is when 2 notes are played at the same time, such as when you are harmonizing.
4. Intervals can be identified by its quality: major, minor, perfect, augmented or diminished. The intervals you will first encounter are perfect 1 (unison), minor/major 2nd, minor/major 3rd, perfect 4th, perfect 5th, minor/major 6th, minor/major 7th, and perfect 8th. To determine an interval quality, there are 2 methods: the Half-Step Method and the Scale Method (refer to #7)
Some additional things to consider:
5. Each interval is made up of a specific number of half steps. You can also think in whole steps too. A half step (semitone) is when you go up or down 1 step to the very next key. It does not matter if it is a white or black key, as long as it is right beside it. A whole step (whole tone) is when you go up or down 2 steps (again, does not matter if it is a white or black key).
6. Intervals are identified by using the lowest note as the tonic (first scale degree of a scale).
7. Below are the 2 methods you can use to identify intervals and its quality.
You can determine the interval and its quality by counting the number of half steps between the two notes.
For example, a minor 2nd interval always consist of two notes that are 1 half step apart. A perfect 8th interval always consists of two notes that are 12 half-steps apart. Refer to the chart below for all intervals.
This method is a quick and easy way to identify your intervals, however we recommend you try the Scale Method too in order to understand intervals more comprehensively.