Understanding Intervals in Music


When it comes to music theory, understanding intervals is akin to unravelling the secrets of a new, and captivating language. In this simple guide, we delve deep into the world of musical intervals and discuss their role with regard to scales and chords.

The Building Blocks of Music

Musical intervals are the fundamental building blocks of music. They represent the spaces or gaps between two notes, measured in semitones or half-steps (the smallest pitch divisions within Western music, and equal to 1 fret on the guitar).

Left-Handed Guitar Fretboard Showing Intervals

By grasping the concept of intervals, we gain the power to shape melody and harmony.

The Chromatic Scale: A Canvas of All Intervals

AA#/BbBCC#/DbDD#/EbEFF#/GbGG#/Ab
The Chromatic Scale

Before we go too far, however, we must have a good understanding of the chromatic scale, a musical canvas that embraces all conceivable pitches within a single octave. This scale spans a palette of twelve unique notes, each separated by a semitone.

This scale serves as our compass in the vast territory of intervals.

Intervals within Scales

Scales are the lifeblood of melodies and harmonies, and their essence is embedded in intervals. Let’s explore a couple of common scales and dissect the intervals that give them their distinct character:

1. The Major Scale

The major scale is a cornerstone of Western music. It contains the following intervals:

  • Root (1)
  • Major Second (2)
  • Major Third (3)
  • Perfect Fourth (4)
  • Perfect Fifth (5)
  • Major Sixth (6)
  • Major Seventh (7)
  • Octave (8)

The major scale follows a precise interval pattern of 2-2-1-2-2-2-1, where each numeral represents the number of semitones between consecutive notes.

2. The Natural Minor Scale

In contrast to the major scale’s exuberance, the natural minor scale evokes a contemplative and introspective mood. Its intervals are as follows:

  • Root (1)
  • Major Second (2)
  • Minor Third (♭3)
  • Perfect Fourth (4)
  • Perfect Fifth (5)
  • Minor Sixth (♭6)
  • Minor Seventh (♭7)
  • Octave (8)

The natural minor scale adheres to a distinctive interval sequence of 2-1-2-2-1-2-2.

Intervals in Chords: Harmony Unveiled

Chords are clusters of notes sounded together. The intervals between their notes govern the quality and emotional resonance of chords. Below, we’ll dissect some fundamental chords and their intervallic structures:

1. The Major Chord

The major chord comprises the following intervals:

  • Root (1)
  • Major Third (3)
  • Perfect Fifth (5)

The intervallic framework of the major chord aligns with a 4-3 structure, signifying that the major third is four semitones above the root, and the perfect fifth is three semitones above the major third. For example, the notes that make up an A Major chord are A (root), C# (Major Third), and E (Perfect Fifth)

2. The Minor Chord

The minor chord comprises of the intervals below:

  • Root (1)
  • Minor Third (♭3)
  • Perfect Fifth (5)

The minor chord’s interval structure is defined by a 3-4 pattern, where the minor third is three semitones above the root, and the perfect fifth is four semitones above the minor third. For example, the notes that make up an A minor chord are A (root), C (Minor Third), and E (Perfect Fifth)

3. The Dominant Seventh Chord

The dominant seventh chord injects tension and anticipation into the musical narrative, featuring the following intervals:

  • Root (1)
  • Major Third (3)
  • Perfect Fifth (5)
  • Minor Seventh (♭7)

The intervallic architecture of the dominant seventh chord is marked by a 4-3-3 arrangement, where the major third is four semitones above the root, the perfect fifth is three semitones above the major third, and the minor seventh is three semitones above the perfect fifth.

4. The Diminished Chord

Intriguing and unresolved, the diminished chord is composed of these intervals:

  • Root (1)
  • Minor Third (♭3)
  • Diminished Fifth (♭5)

The intervallic structure of the diminished chord adheres to a 3-3 pattern, with the minor third three semitones above the root and the diminished fifth three semitones above the minor third.

Musical Intervals

The table below lists all of the intervals within an octave, and corresponding counts in semitones:

IntervalSemitones
Perfect Unison0
Minor Second1
Major Second2
Minor Third3
Major Third4
Perfect Fourth5
Augmented Fourth / Diminished Fifth6
Perfect Fifth7
Minor Sixth8
Major Sixth9
Minor Seventh10
Major Seventh11
Perfect Octave12

Final Thoughts

Musical intervals serve as the essence of scales and chords, enabling musicians to craft melodies and harmonies. Developing an understanding of intervals is pivotal to scales, chords, and ultimately music theory.

About Marty

My name's Marty, I've been tinkering around on left-handed guitars for over 30 years.