Major third each of the intervals are major thirds. Major third In classical music from Western culture, a third is a musical interval encompassing three staff positions (see Interval number for more details), and the major third () is a third spanning four semitones. Along with the minor third, the major third is one of two commonly occurring thirds. It is qualified as "major" because it is the larger of the two: the major third spans four semitones, the minor third three. For example, the interval from C to E is a major third, as the note E lies four semitones above
Ladder of thirds Ladder of thirds A ladder of thirds (coined by van der Merwe 1989, adapted from Curt Sachs) is similar to the circle of fifths, though a ladder of thirds differs in being composed of thirds, major or minor, and may or may not circle back to its starting note and thus may or may not be an interval cycle. Triadic chords may be considered as part of a ladder of thirds. It is a modal frame found in Blues and British folk music. Though a pentatonic type, the melodies come "into being through piling up thirds below and/or above a