Music Theory

Table of Contents


Back in the 16th century, music was written in modes rather than keys

  • Ionian: major scale (starts on C)
  • Dorian: (starts on D)
  • Aoelian: minor scale (starts on A)

Dorian and Aoelian, both popular modes in jazz, lack a leading key (one that's a semitone lower than the tonic), and are known as minor modes

  • All Along the Watchtower

Difference in Intervals

  • Distance between semitones are not equal - if each semitone is exactly 1/12 of an octave, important harmonic intervals do not work.
  • Interval between C-F and D-G are different.
  • In Western music, we use equal temperment - all keys are basically equivalent.


  • C4, 'middle C' of the piano, has a frequency of 261.63 Hz. Each octave above and below doubles and halves that frequency.

  • Pitches for guitar strings are:

    • E4 (1st string)
    • B3 (2st string)
    • G3 (3rd string)
    • D3 (4th string)
    • A2 (5th string)
    • E2 (6th string)

Chord Names

  • Tonic
  • Supertonic
  • Mediant
  • Subdominant
  • Dominant - needs to be dominant. Change V in minor to major. So that it includes the leading tone.
  • Submediant
  • Leading tone

Roman Numerals

  • Capital letter - major.

Major Chords

1 2  3   4  5 6  7
I ii iii IV V vi viidim

Minor Chords

1 2     3   4  5 6  7
i iidim III iv v VI VII
  • Dominant (5th) chord: 3rd is raised to leading note
  • Leading (7th) chord: root is raised to leading note
MM7 major major seventh, 1st and 4th
m7 2 3 6
Mm7 5
dm7 7

Natural minor: Aeolian mode Harmonic minor: raised seventh Melodic minor: raised sixth, along with raised seventh

Minor Diatonic

V (third is raised)
vii (dim)

Dominant (5th)

  • Important to have the leading tone

Codas and Repeats

  • DC al Coda means go to beginning, keep playing until you reach the 'To Coda' sign, then go to Coda.
  • DS al Coda means go to the Segna symbol, keep playing until you reach the 'To Coda' sign, then go to Coda.
  • DS al Fine means go to Segna symbol, then keep playing until the end.


  • Homophony - chords following chords following chords

  • No bass, accompaniment, or melody

  • voice leading - how to move from one chord to the other

  • start open, stay open

  • start close, stay close

  • Sonority (unity) is jeopardised if more than an octave between voices

  • SATB:

    • Soprano (C4 - A5)
    • Alto (G3 - D5) (F5 according to wikipedia)
    • Tenor (C3 - F4) (A4 - Wiki)
    • Bass (E2 - C4)
  • Double the root when voicing for triad

  • Omit the 5th for seventh so that you can keep the doubled root

  • Can change voicing if melody (soprano voice) changes

  • Generally, avoid doubling the leading tone

Keyboard Voicing

Texture type: melody and accompaniment

  • One note in left hand (stem down), three notes in right hand (stem up)
  • Tend to use close structure (right hand needs to be able to reach all SAT)
  • Can add another note in the bass to support it, but it's not usual

7th Chord

Triad + Seventh note

  • Major seventh: 11 semitones above the root
  • Minor seventh: 10 semitones above the root
  • Dominant seventh chord: Major triad + minor seventh (built off the 5th scale degree)
  • Major major: major + major + major
  • half diminished: minor + minor + minor

Voice Leading (18th century)

Types of Motion

  • Parallel (both voices move up/down)
  • Oblique (one voice stays the same)
  • Contrary (voices move in opposite directions)
  • Static (voices stay where they are), e.g. I to vi

Smooth, sonorous, unified, independent

  • IV to V, "Parallel fifths" and parallel octaves. Don't do this
  • Homomorphic, homorhythmic structure
  • For mediant relationship, always has two common tones
  • Avoid the augmented second melodically (a particular voice steps with an interval of an augmented second)
  • Avoid 8ve by contrary montion
  • Avoid direct (hidden) octave between outer voices
  • Can double the third when going from V to VI, to avoid the augmented second (caused by doubling the root (SB))
  • V7 going to VI is a deceptive progression (or a cadence, if it's at the end)


  • Half cadence - anything going to V (feels like you need another phrase/chord to end the piece)
  • Phygian half cadence - only happens in minor: i iv6 (the bass is a semitone above fifth scale degree) V
  • Perfect Authentic cadence - ii°6 V I. Defined by root position V and I chords. Root must be doubled at SB
  • Imperfect Authentic cadence - ii°6 V6 I, or with a melodic third
  • Deceptive cadence - root position V and VI chords (VI instead of resolving to the tonic)

Period Form

Parallel period

  • First phrase - end in half cadence
  • Second phrase - end in full cadence
  • Both very similar, apart from how the cadence is resolved
  • Can also stick a deceptive cadence near the end of the second phrase (H.C., D.C., P.A.C..).

Melodic Writing

  • Point and a point - counterpoint. Hayden and Mozart
  • Step 1: Elaborate the melody
  • "Do it twice, then move on"
  • Retardation

Inversion Notation

Smoothes out the bass, so that it doesn't jump about so much

Comes out of figured bass notation

  • Root is I or I3,5 (root is at bottom), e.g. C E G

  • First inversion is a I6, or I3,6 (third is at bottom), e.g. E G C

  • Second inversion is a I6,4 (fifth is at bottom), e.g. G C E

  • Root of V7 is V7 (root is at bottom)

  • First inversion is V6,5(,3) (third is at bottom)

  • Second inversion is V4,3 (fifth is at bottom)

  • Third inversion is V4,2. (7th is at the bottom)

Don't need to put down every inversion in the chord, just the ones that make it unique

Keep avoiding parallel fifths and octaves (bass and soprano), and try to keep common tone

  • No situation where you can not use a seventh instead of a triad, for the dominant chord
  • Double the fifth for second inversions
  • Try to double the first or the fifth, with first inversions
  • Can double the third (esp for second inversions), for nice voice leading.

Textural reduction

Can be used to:

  • See the harmonic progression more clearly
  • See the harmonic rhythm more clearly
  • See the voice leading more clearly

Second inversions

Second inversion (6,4) chords are less usable than first inversion

  • Can be used for as a 'passing' 64 chord, using the bass to form ascending/descending stepwise bridge

  • Peddle 64: Keep the bass tone as the common tone (used in organ preludes). Using the pedal to hold the note at the bass. Most often used with the 1 4 1 progression

  • Cadential 64: Happens at the end of the piece: anytime you have V resolving to I, can use a I6,4 (used as a decorated V chord) to a V, and then back to a I. Smooth progression, 6th goes to 5th, 4th goes to 3rd.

    • Put it on a strong beat
    • Make it as long as the V chord
  • V4,2 chord almost always resolves to a I6, because the tendency tone of the 4th scale degree is in the bass. Is exposed (in outer voice), so needs to be led properly

Sequential progressions

  • Allows composers to apply a pattern
  • Keyboard voicing: one in the bass, three in the treble

Circle of fifths progression

  • I { /pattern goes here/

  • IV, viidim

  • iii, vi (take previous, move down)

  • ii V (take previous, move down


Examples: Mozart K.545, K. 533

Descending 6-5 progression

Interval between lowest and highest note in I chord is 5th

Interval between lowest and highest note in V6 chord is 6th

{ /pattern starts here. Wow, this is Canon in D's progression, no?/

  • I, V6
  • vi, iii6
  • IV, I6 }

Parallel sixth progression

"Acts like glue"

  • vi6, V6, iv6, iii6, ii6 (technically, can keep doing this until you run out of keys, but usually around 4,5,6)

  • Series of first inversion chords like this is fine

  • Parallel octaves of the bass and the alto usually present, but can alleviate it by shifting around the the tenor and alto

Examples: Mozart K 279, iii

Nonchord tones in classical music

How to get into them? (e.g. by step, or skip?)

How to get out them?

  • Step in, step out in same direction: passing tone. Consecutive passing tones can also occur
  • Step in, step out in opposite direction: neightbour tone
  • Step in, skip out: escape tone
  • Skip in, step out: appoggiatura tone
  • Step in, stay the same: anticipation tone
  • Preparation, suspension (4-3), (or (9-8), (7-6)) must resolve by stepping down, resolution
  • Bass note held, goes in and out of chord: Pedal tone - do nothing, usually on the bass

Diatonic Substitutions

Substituting chords with other chords that are in the same key

  • Similarity between 5 chord and 7 diminished chord
  • i VIIo6 i6 is a common sequence
  • i V65 (5th first inversion of a seventh), i
  • Subtle, but noticeable
  • IV can be substituted for the ii, e.g. i iv V i replaced with i ii°6 V i
  • Substitute chords that are a third apart from each other? No, although there is one other one
  • Substitute a i for a VI chord

Chromatic substitutions

Borrowed chords

Using a minor chord in the major scale. Sounds kind of dreaddy "borrow from the parallel mode" Major and minor are the modes used in classical music. There is also phygrian and dorian, and a bunch of others.

Neapolitan 6 chords


2 chord in minor (diminished) in first inversion, with the root (the top note) lowered, usually denoted 'N6'.

If in Major, you have to lower the fifth as well

Lowered root to leading tone - augmented third - it's okay to do this

Augmented 6 chords

4 chord (subdominant)

Sixth scale degree always at the root 4 types of augmented 6th chords

i iv⁶ V to i It⁶ V

  • It⁶ is the bass, third, augmented 6th
  • Ger⁶ is the bass, third, fifth, augmented 6th
  • Fre⁶ is the bass, third, fourth, augmented 6th

Secondary dominant (V⁶/V)

The dominant of the dominant (2nd), make this by taking the second inversion of the ii6,5 chord, and augment the third (to make it major)

e.g. f,c,d,a to f#,c,d,a, with the f# acting as a leading tone into the root, taken as the current dominant:

c,c,e,g (I)
f#,c,d,a (V⁶/V)
g,b,d,g (V)

"progressions within progressions"

I-V, V-I

"dominant to tonic relationship".

Can use this technique to modulate

For chords that are a 4th apart (upward), should probably use a seventh, otherwise it doesn't really stand out, i.e. V⁷/IV

Alberti Bass

Very common in late 18th century music:

Melody: <c e g>
Bass: c g e g c g e g

Genius... need to use this in my pop music

Don't change:

  1. Always start with the lowest note
  2. Always use 3 notes
  3. Always use chord tones (Final Fantasy doesn't do this...)

Other examples:

<c e g>
c e g e g e g e


  • Write a base line

  • How to write a decent shape

  • Melodic line that moves

  • 1:1 counterpoint:

    • use only chord tones
    • Avoid consecutive notes (makes direction of melodic line static)
    • Avoid direct fifths
    • Leading tones should still be resolved to root
    • Turbulence: avoid jumping from one note to another, then back to the same note
    • Couple of consecutive leaps (of a third) is fine (i.e. 2) - but not too many
  • 2:1 counterpoint - use chord and nonchord tones

    • Going up and down may cause raised or unraised, in melodic minor
    • Nonchord tones can be put in
    • Avoid leaping with more than a fourth. If you do, try to come back down after it
    • Avoid overuse of anticipation. It slows down the motion. Can be used to created motifs.
    • Avoid parallel fifths, as usual
    • Avoid jumping up (by a 4th or more) and then immediately jumping down. Where are you going?

Rounded Binary

defined as:

A A' B A'

Wher A-A' is parallel, A-B is contrasting


  • Allegro: Quick, lively tempo (~120-168 BPM)
  • Augmented triad: Triad consisting of two major thirds (e.g. C, E, G#)
  • Cadences: How phrases are ended
  • Chord tone: Tones that are in the chord
  • Chromatic chord: Ascending/descending pitches proceeding by semitones
  • Common tone approach: While voice leading, try to keep common tones that the chords share. Otherwise, move them by least amount of interval
  • Diatonic chord: chords that are all in the prevailing key
  • Dominant seventh chord: also known as the Major minor seventh chord (major, major, minor)
  • Diminished: Triad consisting of two minor thirds (e.g. C, Eb, Gb)
  • Directed octave: Outer voices leap into an octave interval
  • Escape tone: step in, leap out
  • Equal temperment: every pair of adjacent notes has an identical freqency ratio (12-TET)
  • Fermata: Musical notation - looks like a cyclops eye. Indicates that note shoule be prolonged beyond what its normal duration would indicate
  • Functional harmony:
  • Frustration: the leading tone has not been resolved
  • Homophony: Same rhythm, different pitches (can be homorhythmic homophony (just chords one after the other), or melody and accompaniment)
  • Imperfect authenic cadence:
  • Inpromptu: Free form music composition, as if improvised by the spirit of the moment. Usually for a solo instrument
  • Leading tone: The note before the root note
  • Harmonic rhythm: The rhythm of the harmony, i.e. how fast the harmony progresses, e.g.
  • Harmonic tone:
  • Harmonic progression: series of chord changes forming the underlying harmony of a piece of music
  • Measure: Another word for a bar of music (more of a US term)
  • Melody note: The note that provides the tune (if you were to whistle the music back, you'd whistle the melody notes), usually the soprano (uppermost) voice
  • Neighbour tone: Step in and out, but in opposite directions. Synonyms: auxillary tone
  • Minuet: a slow, stately ballroom dance for two in triple time, popular especially in the 18th century. verb
  • Non-chord tone: tones that are not in the chord, can be used to decorate the chords
  • Outer voice: Soprano or bass
  • PAC: Perfect authentic cadence, going from V to I in major, and V to i in minor.
  • Parallel fifth: Interval of a fifth between e.g. Bass Alto is preserved between chords (undesirable)
  • Parallel octave: Interval of an octave between e.g. Bass Alto is preserved between chords (undesirable)
  • Passing tone: Stepping in and out of the tone in the same direction
  • Passing 64 chord: Using the the bass note of the second inversion as a bridge to create a three note stepwise line, either ascending or descending. Usually goes down more.
  • Picardy third: Resolve to major chord instead of minor tone
  • Phrase: Unit of musical meter that has a complete musical sense on its own, e.g. one cycle of chord progression.
  • Polyphony: Different pitch and rhythm. Bach's well tempered claviar. Voices behaving differently than the others
  • Scale degree: A particular note in a scale, specifying its position relative to the tonic.
  • Slur: Curved line connecting heads of notes, indicating that they should be played without separation (i.e. 'slurring' your words)
  • Suspended: Chord with the third omitted, replaced with the perfect fourth or the major second
  • Tendency tone: tones that need to lead onto a particular tone. Found on 4th (resolves to 3rd) and 7th (resolves to 1st) scale degree (especially when it's in an outer voice).
  • Texture: relationship between voices and instruments. What are the roles of each voice and instrument, in a musical passage?
  • Textural reduction: remove texture that exist, reducing it to a homorhythmic and homophonic piece. (Can't judge voice leading from textural reduction.)
  • Tie: Curved line connecting heads of two notes of the same pitch, indicating that they should be played with a duration equal to sum of individual note values
  • Timbre: tone quality (e.g. quality and colour) - that distinguishes notes of the same pitch and loudness
  • Triad: Set of three notes that can be stacked in thirds, whose members are: root, third and fifth
  • Roman numerial analysis:
  • Voice leading: Strategy for moving from one chord to the next in a harmonic progression