Understanding Intervals in Music Theory: A Practical Guide

Written by Daisie Team

Published on 21 June 2023 8 min read

If you've ever played or listened to music, you've encountered intervals, whether you knew it or not. Intervals are the building blocks of music, and understanding intervals music theory will help you make sense of the melodies and harmonies you love. In this practical guide, we'll explore the different types of intervals, how to identify them, and how they can be used in your own musical creations.

Defining Intervals

Intervals are the distance between two pitches or notes in music. There are two main types of intervals: melodic intervals and harmonic intervals. Let's take a closer look at each one.

Melodic Intervals

Melodic intervals are the distance between two notes that are played one after the other. In other words, they make up the melodies we hear in songs. When you sing a tune or play a melody on your instrument, you're creating a series of melodic intervals.

Harmonic Intervals

Harmonic intervals, on the other hand, occur when two notes are played simultaneously. These intervals create harmony, which is the backbone of chords and the foundation of music. When you strum a guitar or play a chord on the piano, you're producing harmonic intervals that blend together to create a pleasing sound.

Now that we have a basic understanding of melodic and harmonic intervals, let's dive into the different qualities of intervals music theory and learn how to identify them.

Interval Qualities

Interval qualities describe the sound or character of the interval. We have perfect, major, minor, augmented, and diminished intervals. Each quality is determined by the number of half-steps (or semitones) between the two notes. Let's explore these qualities in more detail.

Perfect Intervals

Perfect intervals are found in both major and minor scales and have a stable, consonant sound. They include the unison (same note), the perfect fourth (five half-steps apart), the perfect fifth (seven half-steps apart), and the octave (twelve half-steps apart). When you sing a simple song like "Twinkle, Twinkle, Little Star" or play the first two notes of a power chord on the guitar, you're experiencing perfect intervals.

Major and Minor Intervals

Major and minor intervals are the other building blocks of diatonic (major and minor) scales. Major intervals have a bright, happy sound, while minor intervals have a darker, sadder sound. The most common major and minor intervals are the major and minor seconds, thirds, and sixths.

Major second: 2 half-steps apart
Minor second: 1 half-step apart
Major third: 4 half-steps apart
Minor third: 3 half-steps apart
Major sixth: 9 half-steps apart
Minor sixth: 8 half-steps apart

Augmented and Diminished Intervals

Augmented and diminished intervals are less common but still important for understanding intervals music theory. Augmented intervals are one half-step larger than perfect or major intervals, while diminished intervals are one half-step smaller than perfect or minor intervals. These intervals often create tension or dissonance in music, which can be resolved by moving to a more consonant interval.

Now that we know the different interval qualities, let's learn how to identify specific intervals by counting steps and using key signatures.

Identifying Intervals

Being able to recognize and name intervals is an important skill in intervals music theory. It helps you understand how melodies and harmonies work and can make learning new music easier. Let's look at two methods for identifying intervals: counting steps and using key signatures.

Counting Steps

One way to identify intervals is by counting the steps (or scale degrees) between the two notes. Start by counting the lower note as "1" and continue counting up the scale until you reach the higher note. Here are some examples:

C to E: C(1) - D(2) - E(3) = Major third
G to B: G(1) - A(2) - B(3) = Major third
A to D: A(1) - B(2) - C(3) - D(4) = Perfect fourth

Once you have the number of steps, you can determine the interval quality by counting the number of half-steps (semitones) between the two notes, as explained in the previous section.

Using Key Signatures

Another method to identify intervals is by using key signatures. This can be especially helpful when dealing with notes that have accidentals (sharps or flats). To do this, simply look at the key signature of the piece and determine the interval based on the scale degrees and interval qualities we discussed earlier.

For example, if a piece is in the key of C major and you want to find the interval between E and G, you know that E is the third scale degree and G is the fifth scale degree in C major. Since the perfect fifth is the natural interval between the third and fifth scale degrees in a major scale, the interval between E and G is a perfect fifth.

By mastering both counting steps and using key signatures, you'll be well-equipped to identify intervals in any piece of music. Next, let's explore interval inversions and enharmonic equivalents.

Inversions and Enharmonic Equivalents

As you continue to explore intervals music theory, you'll encounter two essential concepts: inversions and enharmonic equivalents. Understanding these concepts will deepen your knowledge of music theory and improve your ability to analyze and create music.

Interval Inversions

Interval inversions occur when you switch the order of the two notes in an interval, essentially "flipping" the interval. When you invert an interval, its quality remains the same (e.g., major stays major, minor stays minor), but the number of steps changes. Here's a simple way to find the inverted interval:

Subtract the original interval number from 9. For example, if the original interval is a major third (3), the inverted interval is a sixth (9 - 3 = 6).
Keep the same interval quality, but adjust it accordingly if necessary (e.g., major stays major, minor stays minor, perfect stays perfect).

Here are some examples of interval inversions:

Major third (C to E) becomes a minor sixth (E to C)
Perfect fifth (G to D) becomes a perfect fourth (D to G)
Minor seventh (A to G) becomes a major second (G to A)

Understanding interval inversions is important for analyzing chords and harmonies, as well as for transposing music.

Enharmonic Equivalents

Enharmonic equivalents are pairs of notes that sound the same but are written differently. This concept is important in intervals music theory because it helps us recognize that some intervals may look different on the staff but are still the same interval. Common examples of enharmonic equivalents include:

C# and Db
F# and Gb
B# and C

When identifying intervals, it's crucial to consider enharmonic equivalents. For example, the interval between C and Db is a minor second, but if the Db is written as a C#, the interval becomes an augmented unison, even though the two notes sound the same.

Now that you have a solid understanding of interval inversions and enharmonic equivalents, let's look at some practical applications of intervals music theory in melodies, harmonies, and transposition.

Practical Applications

Intervals music theory is not just an abstract concept; it has many practical applications in creating, performing, and analyzing music. Let's dive into some ways you can apply your knowledge of intervals to chords and harmony, melodies and improvisation, and transposition.

Chords and Harmony

Intervals are the building blocks of chords and harmony. By stacking intervals on top of each other, you create chords, which are the foundation of harmony in music. For example:

A major triad consists of a major third (e.g., C to E) and a perfect fifth (C to G).
A minor triad consists of a minor third (e.g., A to C) and a perfect fifth (A to E).
A dominant seventh chord consists of a major third (e.g., G to B), a perfect fifth (G to D), and a minor seventh (G to F).

By understanding the intervals that make up chords, you can analyze and create harmonic progressions, helping you enrich your compositions and improvisations.

Melodies and Improvisation

Intervals are also an essential component of melodies. By combining different intervals, you can create a wide range of melodic patterns and shapes. In improvisation, understanding intervals can help you navigate the musical landscape and create melodies that fit the harmony. For example, if you know a chord progression consists of major and minor triads, you can use major and minor thirds, as well as perfect fifths, to create melodies that blend with the harmony.

Additionally, being aware of intervallic relationships can help you recognize melodic patterns and structures in the music you listen to and perform—making it easier to learn new songs and develop your ear training skills.

Transposition

Transposition is the process of changing the key of a piece of music by shifting all the notes by a consistent interval. A solid understanding of intervals music theory is crucial for transposing music accurately. When you transpose, you must maintain the same interval relationships between the notes to preserve the harmony and melody of the piece.

For example, if you want to transpose a melody from C major to G major, you would shift every note up by a perfect fifth. A C major scale (C, D, E, F, G, A, B) would become a G major scale (G, A, B, C, D, E, F#) when transposed up a perfect fifth. By understanding intervals, you can transpose music to fit the range of different instruments or accommodate the vocal range of a singer.

Now that you have a firm grasp of intervals music theory and its practical applications, you may be interested in exploring further resources to deepen your understanding and improve your skills.

Resources for Further Study

Intervals music theory is a fundamental aspect of music, and there are countless resources available to help you further your knowledge and skills. Here are some recommendations for books, online courses, and apps and software that can help you dive deeper into the world of intervals and music theory.

Music Theory Books

Books are a great way to learn more about intervals music theory and other music theory concepts at your own pace. Some popular music theory books include:

The Complete Musician by Steven G. Laitz
Music Theory for Dummies by Michael Pilhofer and Holly Day
The Everything Music Theory Book by Marc Schonbrun

These books offer detailed explanations, examples, and exercises to help you develop a strong foundation in music theory.

Online Courses

Online courses can be an excellent way to learn intervals music theory and other music theory concepts with the guidance of experienced instructors. Some popular platforms offering music theory courses include:

Coursera: Offers a variety of music theory courses, from beginner to advanced levels, taught by professors from renowned music schools.
Udemy: Provides a wide range of music theory courses, often with a focus on specific instruments or genres.
MusicTheory.net: A free online resource with lessons, exercises, and tools to help you learn music theory concepts, including intervals.

These platforms offer interactive learning experiences, often with quizzes, assignments, and instructor feedback to help you solidify your understanding.

Apps and Software

There are many apps and software programs designed to help you learn and practice intervals music theory. Some popular options include:

Tenorshare Music Theory: An app that offers lessons, exercises, and quizzes on various music theory topics, including intervals.
EarMaster: A comprehensive ear training software that includes interval recognition exercises, as well as exercises for chords, scales, and rhythm.
Perfect Ear: An app that provides interval training exercises, along with lessons and quizzes on other music theory concepts.

These apps and software programs offer a convenient and engaging way to learn and practice intervals music theory, helping you develop your ear training and overall musicianship skills.

By exploring these resources and continuing to practice your understanding of intervals, you'll be well on your way to mastering intervals music theory and applying it to your musical journey.

If you're intrigued by the connection between music and visuals, we highly recommend exploring 'Creative Crossovers: Music & Visuals' workshop by Jarrett Lampley. This workshop will provide you with unique insights and techniques to enhance your creative process by combining the powerful elements of music and visuals.