Notes on Fundamentals of Music Theory (2)


The previous week’s notes are here

Notes for Week 2

Sharps and Flats

  • For major scales that does not start on a C note (i.e. C Major), to follow a Tone-Tone-Semitone-Tone-Tone-Tone-Semitone pattern (standard for a major scale), black keys on a keyboard are put to use.
    • Sharp(): a semitone higher (sharper) than a note
    • Flat (): a semitone flatter (lower) than a note
    • E♯ is the same as F♭
    • Scale needs one of each note name
    • and symbols are written after each letter note name, or before a note on the stave

Keys and Key Signatures

  • Convention and noation: marking corresponding ledgers or spaces on a stave with sharps and flats makes a piece of music on the stave easily recognizable in terms of its tonic, known as key signatures.

    • A key signature will never contain both flats and sharps
  • Each major has a unique signature

  • Circle of fifths: incrementing clockwise 1 sharp each step

  • Accidentals: to notes outside the major, accidental sharps and flats need to be placed in front of notes.

    • Accidentals are effective for the whole bar, and a natural () sign needs to be placed in front of the next note of the same name within a bar to cancel out the accidental.

Minor Keys

  • Natural (relative) minor scale: scales toning on the sixth of a major scale
  • B natural minor scale has all the notes of D natual major
  • Leading note: the seventh note in a scale
  • Dominant note: the fifth note (revision)
  • Accordingly, the tonic of a relative (natural) major scale is a minor third of a relative minor scale, e.g. C is the relative major of A minor, as C is 3 semitones after A
  • Harmonic minor scale: natural minor scale with the seventh note raised 1 semitone
  • Melodic minor scale: the ascendant form (sixth and seventh raised 1 semitone) being different from the descendant form (coming down in the natural scale form)


  • Different qualities (starting from the tonic)

    • Perfect: unison, fourth, fifth, octave
    • Major: second, third, sixth, seventh
    • Minor: 1 semitone lower than a major interval
    • Augmented: 1 semitone higher than a perfect interval
    • Diminished: 1 semitone lower than a perfect interval
  • Quality of intervals in major scales/keys

Interval Quality
Unison Perfect
2nd Major
3rd Major
4th Perfect
5th Perfect
6th Major
7th Major
8ve (Octave) Perfect
  • Major interval:

    • 1 semitone higher: augmented
    • 1 semitone lower: minor
  • Perfect interval:

    • 1 semitone higher: augmented
    • 1 semitone lower: diminished
  • Minor interval:

    • 1 semitone higher: major
    • 1 semitone lower: diminished
  • Compound intervals: intervals greater than an octave are related to their simpler equivalents.

    • An 11th is a perfect 4th, hence a compound perfect 4th

Ledger Lines and Clefs

  • Clefs are used to indicate which range of pitches the standard stave lines and spaces should represent
  • Four major clefs:
    • Treble
    • Bass
    • Alto
    • Tenor
  • If two staves are grouped by a brace ({), the meeting point between these two clefs will be the first ledger line below the upper stave, and the first ledger line above the lower stave