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Chapter 5 - Harmonic Organization 1: Intervals, Triads, and Seventh Chords

  • Harmony - The way notes are simultaneously sounded, creating a vertical element to music.

  • Counterpoint - A single melody line or linear voice added to another line or voice.

Intervals

  • Interval - The distance between two pitches.

    • They can be melodic or harmonic.

    • The exact interval size is described by quantity and quality.

    • Quality - Expressed by a number and determined by counting the distance between one letter name and the next letter name.

Identifying Interval Quality

  • All intervals built from the tonic up to notes within a major scale are either major or perfect.

  • Perfect intervals

    • Unison

    • Perfect fourth

    • Perfect fifth

    • Perfect eighth

  • Major intervals

    • Major second

    • Major third

    • Major sixth

    • Major seventh

  • A minor interval is one-half step smaller than major.

  • Diminished interval - An interval that is one-half step smaller than perfect or minor.

  • Augmented interval - An interval that is one-half step larger than major or perfect.

  • Enharmonic intervals - They sound the same but are spelled differently and function differently.

  • Doubly augmented interval - When a major or perfect interval is made one whole step larger without changing the letter names of the pitches.

  • Doubly diminished interval - When a minor or perfect interval is made one whole step smaller without changing the letter names of the pitches.


If-Then Intervals

  • If the top note is in the major key of the bottom note, then it is major or perfect.

  • If the top note is a half step lower than the diatonic note would be, then it is a minor or diminished interval.

  • If the top note is a half step higher than the diatonic note would be, then it is an augmented interval.

  • If an interval is perfect, then both top and bottom pitches are in the other’s major key.

  • If the same accidental is added to both upper and lower pitches, then the interval remains the same.

  • If an accidental is added only to the bottom pitch, then the accidental has the opposite effect than when added to the note above:

    • If a flat is added to the lower pitch, the interval is larger.

    • If a sharp is added to the lower pitch, the interval is smaller.

  • If the lower notes doesn’t represent a standard key, then determine what the interval would be without the accidental and adjust.


  • Simple intervals - Intervals that are one octave or smaller in quantity.

    • They are expanded to a compound interval by adding seven

  • Compound intervals - Intervals that are larger than an octave.

    • They are reduced to a simple interval by subtracting seven.

  • Inverted intervals - Intervals are inverted by transferring the lower note an octave higher or by transferring the higher note an octave lower.

    • Major intervals invert to minor intervals.

    • Augmented intervals invert to diminished intervals.

  • The rule of nine - When any simple interval is inverted, the sum of the ascending and descending intervals must add up to nine.

    • A second inverts to a seven.

    • A third inverts to a sixth.

    • A fourth inverts to a fifth.

  • Consonant intervals - Stable

  • Dissonant intervals - Unstable, the impression of activity or tension.

  • Resolution - The motion of the dissonant interval to the consonant that acts as its goal.

  • Within any four-part composition, these intervals may exist:

    • A-S, Alto and Soprano

    • T-S, Tenor and Soprano

    • T-A, Tenor and Alto

    • B-S, Bass and Soprano

    • B-A, Bass and Alto

    • B-T, Bass and Tenor

Triads

  • Chord - A group of pitches that forms a single harmonic idea.

  • Triad - A three-note chord made up of two intervals stacked in thirds.

  • Root - The lower note of the chord.

  • Third - The middle note because it’s an interval of a third above the root.

  • Fifth - The upper note, it’s a fifth above the root.

Building Triads

  • Tertian harmony - Harmony built on thirds.

  • To build a triad:

    • Build the snowman in thirds above the root.

    • Identify the quality of the lower third as a major or minor.

    • Identify the quality of the fifth as perfect, diminished, or augmented.

    • Identify the chord with the pitch name letter (the root of the snowman).

    • Identify the quality of the triad

HC

Chapter 5 - Harmonic Organization 1: Intervals, Triads, and Seventh Chords

  • Harmony - The way notes are simultaneously sounded, creating a vertical element to music.

  • Counterpoint - A single melody line or linear voice added to another line or voice.

Intervals

  • Interval - The distance between two pitches.

    • They can be melodic or harmonic.

    • The exact interval size is described by quantity and quality.

    • Quality - Expressed by a number and determined by counting the distance between one letter name and the next letter name.

Identifying Interval Quality

  • All intervals built from the tonic up to notes within a major scale are either major or perfect.

  • Perfect intervals

    • Unison

    • Perfect fourth

    • Perfect fifth

    • Perfect eighth

  • Major intervals

    • Major second

    • Major third

    • Major sixth

    • Major seventh

  • A minor interval is one-half step smaller than major.

  • Diminished interval - An interval that is one-half step smaller than perfect or minor.

  • Augmented interval - An interval that is one-half step larger than major or perfect.

  • Enharmonic intervals - They sound the same but are spelled differently and function differently.

  • Doubly augmented interval - When a major or perfect interval is made one whole step larger without changing the letter names of the pitches.

  • Doubly diminished interval - When a minor or perfect interval is made one whole step smaller without changing the letter names of the pitches.


If-Then Intervals

  • If the top note is in the major key of the bottom note, then it is major or perfect.

  • If the top note is a half step lower than the diatonic note would be, then it is a minor or diminished interval.

  • If the top note is a half step higher than the diatonic note would be, then it is an augmented interval.

  • If an interval is perfect, then both top and bottom pitches are in the other’s major key.

  • If the same accidental is added to both upper and lower pitches, then the interval remains the same.

  • If an accidental is added only to the bottom pitch, then the accidental has the opposite effect than when added to the note above:

    • If a flat is added to the lower pitch, the interval is larger.

    • If a sharp is added to the lower pitch, the interval is smaller.

  • If the lower notes doesn’t represent a standard key, then determine what the interval would be without the accidental and adjust.


  • Simple intervals - Intervals that are one octave or smaller in quantity.

    • They are expanded to a compound interval by adding seven

  • Compound intervals - Intervals that are larger than an octave.

    • They are reduced to a simple interval by subtracting seven.

  • Inverted intervals - Intervals are inverted by transferring the lower note an octave higher or by transferring the higher note an octave lower.

    • Major intervals invert to minor intervals.

    • Augmented intervals invert to diminished intervals.

  • The rule of nine - When any simple interval is inverted, the sum of the ascending and descending intervals must add up to nine.

    • A second inverts to a seven.

    • A third inverts to a sixth.

    • A fourth inverts to a fifth.

  • Consonant intervals - Stable

  • Dissonant intervals - Unstable, the impression of activity or tension.

  • Resolution - The motion of the dissonant interval to the consonant that acts as its goal.

  • Within any four-part composition, these intervals may exist:

    • A-S, Alto and Soprano

    • T-S, Tenor and Soprano

    • T-A, Tenor and Alto

    • B-S, Bass and Soprano

    • B-A, Bass and Alto

    • B-T, Bass and Tenor

Triads

  • Chord - A group of pitches that forms a single harmonic idea.

  • Triad - A three-note chord made up of two intervals stacked in thirds.

  • Root - The lower note of the chord.

  • Third - The middle note because it’s an interval of a third above the root.

  • Fifth - The upper note, it’s a fifth above the root.

Building Triads

  • Tertian harmony - Harmony built on thirds.

  • To build a triad:

    • Build the snowman in thirds above the root.

    • Identify the quality of the lower third as a major or minor.

    • Identify the quality of the fifth as perfect, diminished, or augmented.

    • Identify the chord with the pitch name letter (the root of the snowman).

    • Identify the quality of the triad