Just major third.Pythagorean major third, i.e. a ditoneComparison, in cents, of intervals at or near a major thirdHarmonic series, partials 1–5 numbered Playⓘ.
In
whole steps.[1] 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 interval 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 C, and there are three staff positions from C to E. Diminished and augmented thirds
span the same number of staff positions, but consist of a different number of semitones (two and five).
The intervals from the
scale degrees of a major scale are called major.[2]
The major third may be derived from the harmonic series as the interval between the fourth and fifth harmonics.
The
scale degrees
.
The major chord also takes its name from the presence of this interval built on the chord's root (provided that the interval of a perfect fifth from the root is also present or implied).
A major third is slightly different in different musical tunings: in just intonation it corresponds to a pitch ratio of 5:4 (playⓘ) (fifth harmonic in relation to the fourth) or 386.31 cents; in equal temperament, a major third is equal to four semitones, a ratio of 21/3:1 (about 1.2599) or 400 cents, 13.69 cents wider than the 5:4 ratio. The older concept of a ditone (two 9:8 major seconds) made a dissonantly wide major third with the ratio 81:64 (about 1.2656) or 408 cents (playⓘ). The septimal major third is 9:7 (435 cents), the undecimal major third is 14:11 (418 cents), and the tridecimal major third is 13:10 (452 cents).
In equal temperament three major thirds in a row are equal to an octave (for example, A♭ to C, C to E, and E to G♯; G♯ and A♭ represent the same note). This is sometimes called the "
subharmonic
, is less than an octave. For example, three 5:4 major thirds from C is B♯ (C to E to G♯ to B♯) (B♯). The difference between this just-tuned B♯ and C, like that between G♯ and A♭, is called the "enharmonic diesis", about 41 cents (the inversion of the 125/64 interval: playⓘ)).
they were considered dissonances unusable in a stable final sonority.
A
enharmonically equivalent to a major third (that is, it spans the same number of semitones). For example, B–D♯ is a major third; but if the same pitches are spelled B and E♭, the interval is instead a diminished fourth. B–E♭ occurs in the C harmonic minor scale
