Notes on Fundamentals of Music Theory (2)

Prologue

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)

Intervals

• 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