Intervals & Chords

Interval: a combination of two notes


a. Interval names: The name of an interval (third, fifth, etc.) describes the distance between the 2 pitches in the following manner:

  • Unison: no distance (could be played by two different instruments)
  • Minor Second: one semitone
  • Major Second: two semitones
  • Minor Third: three semitones
  • Major Third: four semitones
  • Perfect Fourth: five semitones
  • Tritone: six semitones
  • Perfect Fifth: seven semitones
  • Minor Sixth: eight semitones
  • Major Sixth: nine semitones
  • Minor Seventh: ten semitones
  • Major Seventh: eleven semitones
  • Octave: twelve semitones
  • Augmented: one semitone added
  • Diminished: one semitone subtracted

(The designation of "augmented" or "diminished" intervals is based on the spelling of the notes: i.e. where they are placed on the staff, which is determined by the scale or key or chord being used.)


b. Harmonic intervals: notes played simultaneously thus creating harmony

c. Melodic intervals: notes played one after the other thus creating melody

d. Dissonance: two or more notes whose overtones conflict or clash

e. Consonance: two or more notes with some overtones in common


Chords (any combination of tones played simultaneously)

a. Triad: a three-note chord built of two stacked thirds

b. A Major triad’s three notes are root, major third and perfect fifth (first, third, and fifth notes of a major scale)

c. A Minor triad’s three notes are root, minor third, and perfect fifth (first, third, and fifth notes of a minor scale)

d. Seventh chords: triads with an added seventh (first, third, fifth, and seventh notes of a scale)

e. Inversions: chords in which the root tone is not the lowest note. 

f. Other chords: Chords which contain additions or alterations.

g. Arpeggio: (harp-like) the notes of a chord played or sung in sequence, one after the other, rather than simultaneously

h. Tone Cluster: three or more adjacent tones, played simultaneously