Intro to Music Theory Unit 5 ReviewIntervals

What Are Intervals?

• Intervals are the distances between two pitches in music
• Measured by the number of half steps or whole steps between the two notes
• Intervals can be melodic (notes played sequentially) or harmonic (notes played simultaneously)
• Intervals are a fundamental concept in music theory used to build scales, chords, and melodies
• Understanding intervals helps musicians analyze and create music
• Intervals can be described by their quality (major, minor, perfect, augmented, or diminished) and size (unison, second, third, etc.)
• The smallest interval is a half step (semitone) and the largest interval within an octave is a major seventh

Types of Intervals

• There are two main types of intervals: melodic and harmonic
  • Melodic intervals occur when two notes are played sequentially (one after the other)
  • Harmonic intervals occur when two notes are played simultaneously (at the same time)
• Intervals can also be categorized as simple or compound
  • Simple intervals are intervals within one octave (unison up to a major seventh)
  • Compound intervals are intervals larger than an octave (octave, ninth, tenth, etc.)
• Intervals can be further classified by their quality and size
  • Quality refers to whether an interval is major, minor, perfect, augmented, or diminished
  • Size refers to the number of letter names between the two notes (unison, second, third, etc.)
• Consonant intervals are intervals that sound stable and pleasing (perfect unison, perfect fifth, perfect fourth, major and minor thirds and sixths)
• Dissonant intervals are intervals that sound unstable and create tension (minor second, major second, minor seventh, major seventh, and all augmented and diminished intervals)

Measuring Intervals

• Intervals are measured by counting the number of letter names between the two notes (including both notes)
  • For example, from C to E is a third because it includes three letter names (C, D, E)
• The quality of an interval is determined by the number of half steps between the two notes
  • Major intervals have a specific number of half steps (major second: 2, major third: 4, major sixth: 9, major seventh: 11)
  • Perfect intervals also have a specific number of half steps (perfect unison: 0, perfect fourth: 5, perfect fifth: 7, perfect octave: 12)
• To determine the number of half steps in an interval, count the number of semitones on a piano keyboard or use the chromatic scale
• Enharmonic intervals are intervals that sound the same but are spelled differently (C# to E and Db to E are both major thirds)
• Diatonic intervals are intervals found within a major or minor scale, while chromatic intervals involve notes outside the scale

Major and Perfect Intervals

• Major intervals include major seconds, major thirds, major sixths, and major sevenths
  • Major seconds have 2 half steps, major thirds have 4 half steps, major sixths have 9 half steps, and major sevenths have 11 half steps
• Perfect intervals include perfect unisons, perfect fourths, perfect fifths, and perfect octaves
  • Perfect unisons have 0 half steps, perfect fourths have 5 half steps, perfect fifths have 7 half steps, and perfect octaves have 12 half steps
• Major and perfect intervals are considered consonant and stable
• The interval between the first and last note of a major scale is always a perfect octave
• The interval between the first and fifth note of a major scale is always a perfect fifth
• The interval between the first and fourth note of a major scale is always a perfect fourth

Minor, Augmented, and Diminished Intervals

• Minor intervals are one half step smaller than their major counterparts
  • Minor seconds have 1 half step, minor thirds have 3 half steps, minor sixths have 8 half steps, and minor sevenths have 10 half steps
• Augmented intervals are one half step larger than their major or perfect counterparts
  • Augmented unisons have 1 half step, augmented seconds have 3 half steps, augmented fourths have 6 half steps (also known as a tritone), augmented fifths have 8 half steps, and augmented sixths have 10 half steps
• Diminished intervals are one half step smaller than their minor or perfect counterparts
  • Diminished seconds have 0 half steps (enharmonic to a perfect unison), diminished thirds have 2 half steps, diminished fourths have 4 half steps, diminished fifths have 6 half steps (also known as a tritone), diminished sixths have 7 half steps, diminished sevenths have 9 half steps
• Minor, augmented, and diminished intervals are considered dissonant and create tension in music

Interval Inversions

• Inverting an interval means flipping the two notes around a central axis, usually within an octave
• To invert an interval, move the lower note up an octave or move the higher note down an octave
• Interval inversions always add up to nine (a second inverts to a seventh, a third to a sixth, a fourth to a fifth, and vice versa)
• Perfect intervals remain perfect when inverted (perfect fourth inverts to perfect fifth)
• Major intervals become minor when inverted, and minor intervals become major (major third inverts to minor sixth)
• Augmented intervals become diminished when inverted, and diminished intervals become augmented (augmented fourth inverts to diminished fifth)
• Understanding interval inversions helps with recognizing and building chords and harmony in music

Ear Training for Intervals

• Ear training is the practice of identifying intervals by ear
• Developing a strong sense of relative pitch is essential for recognizing intervals
• Associating intervals with familiar songs can help with interval recognition (perfect fifth: "Twinkle, Twinkle, Little Star"; perfect fourth: "Here Comes the Bride"; major third: "When the Saints Go Marching In")
• Practicing interval recognition regularly with exercises and drills can improve ear training skills
• Singing intervals can help internalize the sound and feel of each interval
• Transcribing melodies and harmonies by ear can also improve interval recognition skills
• Online resources and apps (musictheory.net, Teoria, Tenuto) offer interval ear training exercises and quizzes

Applying Intervals in Music

• Intervals form the building blocks of scales, chords, and melodies in music
• Understanding intervals helps with analyzing and creating harmony and melody
• Intervals can be used to create different moods and emotions in music (minor intervals for sad or melancholic, major intervals for happy or uplifting)
• Composers use intervals to create tension and resolution in music (dissonant intervals resolving to consonant intervals)
• Intervals are used in all genres of music, from classical to pop, rock, and jazz
• Recognizing intervals can help with sight-reading and learning new pieces of music more quickly
• Intervals are essential for transposing music from one key to another
• Improvising melodies and solos relies heavily on understanding and using intervals effectively