skip to main content

Music Theory Notes

Make sound good.

Published 2024/06/03

Updated 2024/09/29

Table of Contents

    Scales

    Diatonic Scales

    Each note letter is only used once in a scale.

    (This convention sometimes leads to notes being described with unexpected sharps and flats, e.g. C Minor Scale has a Bb instead of A.)

    a diatonic scale is any heptatonic scale (scale with 7 notes per octave) that includes five whole steps and two half steps in each octave, in which the two half steps are separated from each other by either two or three whole steps. This pattern ensures that all the half steps are maximally separated from each other (i.e. separated by at least two whole steps).

    The seven pitches of any diatonic scale can also be obtained by using a chain of six perfect fifths.

    if one of the two versions is a perfect interval, the other is called either diminished (i.e. narrowed by one semitone) or augmented (i.e. widened by one semitone).

    Otherwise, the larger version is called major, the smaller one minor.

    Within a diatonic scale, unisons and octaves are always qualified as perfect,

    fourths as either perfect or augmented,

    fifths as perfect or diminished,

    and all the other intervals (seconds, thirds, sixths, sevenths) as major or minor.

    Major Scale

    Also known as the Ionian Mode.

    (whole step or half step)
(semitone steps)
(total semitones)
(scale degree, b or # relative to major)
(note letter)
(scale names, mode name)

 --W--W-H--W--W--W-H
 --2--2-1--2--2--2-1
0--2--4-5--7--9--11-12
1--2--3-4--5--6--7-1
C--D--E-F--G--A--B-C
C Major, Ionian Mode

    C Major (and its relative minor scale, A Minor) doesn't have any sharps or flats.

    Minor Scales

    There are 3 types of minor scale:

    • natural
    • harmonic
    • melodic
    Natural Minor Scale

    The default minor scale. Assume this minor scale if the type of minor scale is not specified.

     --W-H --W--W-H --W --W
 --2-1 --2--2-1 --2 --2
0--2-3 --5--7-8 --10--12
1--2-b3--4--5-b6--b7--1
C--D-Eb--F--G-Ab--Bb--C
C Natural Minor, C Minor, Aeolian Mode
    Harmonic Minor Scale

    The seventh scale degree is raised by a half step (back to how it was in the Major Scale, because that interval sounds good).

     --W-H --W--W-H ---WH-H
 --2-1 --2--2-1 ---3 -1
0--2-3 --5--7-8 ---11-12
1--2-b3--4--5-b6---7 -1
C--D-Eb--F--G-Ab---B -C
C Harmonic Minor
    Melodic Minor Scale

    Descending: identical to natural minor.

    Ascending: raised sixth and seventh scale degrees (so that there isn't a 3 semitone jump).

     --W-H --W--W--W--W-H
 --2-1 --2--2--2--2-1
0--2-3 --5--7--9--11-12
1--2-b3--4--5--6--7-1
C--D-Eb--F--G--A--B-C
C Melodic Minor

    They share the flat third scale degree (b3).

    Major -> Natural Minor

    1 2 b3 4 5 b6 b7 1

    Major -> Harmonic Minor

    1 2 b3 4 5 b6 7 1

    Major -> Melodic Minor

    1 2 b3 4 5 6 7 1

    A Major to A Minor is the parallel minor.

    C Major to A Minor is the relative minor.

    C Major

    C D E F G A B C

    C Minor

    C D Eb F G Ab Bb C

    A Major

    A B C# D E F# G# A

    A Minor (same notes as C Major)

    A B C D E F G A

    Relative minor starts from the 6th note of the major scale.

    Or, relative major starts from the 3rd note of the minor scale.

    In other words, the relative minor is 3 semitones below, or 9 semitones above, the major.

    relative minor is a natural minor scale.

    Natural minor scales share a key signature with a relative major key.

    The primary difference between major scales and minor scales is the third scale degree. A major scale always has a natural third (or major third). A minor scale never has a major third.

    In practice, you can add any note as a tension to a minor scale except for a major third.

    For example, if you are playing a D minor scale, almost any note can arguably sound good in this scale except for F♯. If you play an F♯, the scale instantly takes on a major tonality.

    Other Scales

    Chromatic Scale

    All possible notes.

    12 notes, then repeat.

    -H-H-H-...-H- (whole step or half step)
1-2-3-...-12-1 (note number)
0-1-2-...-12-13 (total semitones)
C, C#, D, D#, E, F, F#, G, G#, A, A#, B, C
(note name, from C for piano)
E, F, F#, G, G#, A, A#, B, C, C#, D, D#, E
(note name, from E for guitar)

    Pentatonic Scale

    5 notes. Remove the notes that are only a semitone away, so that none of the notes clash and you can play them in any order.

    Major -> Pentatonic

    1 2 3 5 6 (1)

    Major -> Minor Pentatonic

    1 b3 4 5 b7 (1)

    Blues Scale

    Minor Pentatonic + b5.

    Major -> Blues

    1 b3 4 b5 6 b7 (1)

    Scale Degrees

    Scale degree: the position of a note relative to the tonic.

    I  ii  iii  IV  V  vi  vii° I

    Uppercase: major

    Lowercase: minor

    Lowercase°: diminished

    Uppercase+: augmented

    I: major

    ii: minor

    iii: minor

    IV: major

    V: major

    vi: minor

    vii° (a.k.a. vii_b5): diminished (a.k.a. minor b5)

    I: major

    The eight degrees of the scale are also known by traditional names:

    1st: Tonic (key note)

    2nd: Supertonic

    3rd: Mediant

    4th: Subdominant

    5th: Dominant

    6th: Submediant

    7th: Leading Note/Tone OR Subtonic

    8th: Tonic (octave)

    "subtonic" is used when the interval between it and the tonic in the upper octave is a whole step (i.e. natural minor scale).

    "leading note" is used when that interval is a half-step (i.e. major scale).

                          Tonic
      (-2nd) Subtonic --|-- (+2nd) Supertonic
   (-3rd) Submediant ---|--- (+3rd) Mediant
(-5th) Subdominant -----|----- (+5th) Dominant

    Modes

    I--II--III-IV--V--VI--VII-I
 --W --W  -H --W--W --W  -H

    (starting note): (name of mode)

    I: Ionian (Major scale)

    ii: Dorian

    iii: Phrygian

    IV: Lydian

    V: Mixolydian

    vi: Aeolian (Natural Minor scale)

    vii: Locrian

    mode: which note to start from in the loop.

    Chords

    Building Chords

    Major Chord

    1, 3, 5 (scale degree of major scale)
 -4-3- (steps in semitones)
0, 4, 7 (total semitones)

    Minor Chord

    1, b3, 5
 -3-4-
0, 3, 7

    Augmented Chord

    1, 3, 5#
 -4-4-
0, 4, 8

    Diminished Chord

    1, b3, b5
 -3-3-
0, 3, 6

    Dominant Seventh Chord

    1, 3, 5, b7
 -4-3-3-
0, 4, 7, 10

    Suspended 2nd Chord

    1, 2, 5
 -2-5-
0, 2, 7

    Sus 4 Chord

    1, 4, 5
 -5-2-
0, 5, 7

    Major 7 Sus 2 Chord

    1, 2, 5, 7
 -2-5-2-
0, 2, 7, 11

    (Dmaj7sus2 sounds good)

    Chord Progressions

    These are some common chord progressions.

    I-V-vi-IV (scale degree)
0 7 9  5 (total semitones)
    I-IV-V-IV
0 5  7 5
    ii-V-I
2  7 0
    I-vi-IV-V
0 9  5  7
    I-bVII-I
0 10   0

    12 Bar Blues

    I-I-I-I
0 0 0 0

IV-IV-I-I
5  5  0 0

V-IV-I-I
7 5  0 0

    Canon

    I-V-vi-iii
0 7 9  4

IV-I-IV-V
5  0 5  7

    Royal Road

    IV-V-iii-vi
5-0-5-7

    David Bennett Piano video about Royal Road progression.

    Popular in Japanese music.

    Variations: all 7th chords.

    Guitar Notes Math

    E-A-D-G-B-E

    -5-5-5-4-5-

    0, 5, 10, 15, 19, 24 semitones total (i.e. 2 octaves)

    E, F, F#, G, G#, A - 5 semitones

    A, A#, B, C, C#, D - 5 semitones

    D, D#, E, F, F#, G - 5 semitones

    G, G#, A, A#, B - 4 semitones

    B, C, C#, D, D#, E - 5 semitones

    E, F, F#, G, G#, A, A#, B, C, C#, D, D#, E

    E Major Scale

    E, F#, G#, A, B, C#, D#, E

    Make the C Major Scale

    Barre on fret 1 for 1st and 2nd string.

    E A D G B E
       |--> one semitone up for 1st and 2nd string
E A D G C F
    C  D E F  G A B (C Major scale)
2# 4 6 1# 3 5 2 (string number)