Major 6th

General info

Interval

Major 6th

Quality

Major

Semitones

9

Degree distance

6 degrees

Degree

6

Interval structure

Lower note

C (261.6 Hz)

Lower note role

Root

Upper note

A (440.0 Hz)

Upper note role

Major sixth (6)

Degree formula

I

VI

Semitone formula

9 semitones (4.5 tones)

Interval construction

Interval formula

M6

Brief explanation

A major sixth spans nine semitones and inverts to a minor third. It is a wide melodic interval and an imperfect consonance when sounded simultaneously.

Interval notes

Consonance / dissonance

Sonority

Imperfect consonance

Explanation

A major sixth is an imperfect consonance. It spans a wider register than a third but retains the same consonance class as its inversion, the minor third.

How the interval sounds

Tendencies & resolutions

As a consonance, a major sixth needs no independent resolution. A wide melodic leap is often followed by stepwise motion in the opposite direction, but this is a voice-leading convention rather than an inherent requirement.

Harmonic context

The major 6th does not appear in standard triads, but is present in 6th chords (C6) and melodic minor. In major scales (Ionian, Dorian, Lydian, Mixolydian), the 6th is a characteristic degree. In jazz, 6th chords (C6, Cm6) are a common triad substitute.

Interval inversion

Inverts to

Minor 3rdm3

Quality change

Major

minor

Inversion rule

When inverting a major 6th, the lower note moves up an octave. 9 semitones (M6) become 3 semitones — a minor 3rd (m3).

Related intervals