| Inverse | minor third |
|---|---|
| Name | |
| Other names | septimal major sixth, supermajor sixth, major hexachord, greater hexachord, hexachordon maius |
| Abbreviation | M6 |
| Size | |
| Semitones | 9 |
| Interval class | 3 |
| Just interval | 5:3, 12:7 (septimal), 27:16[1] |
| Cents | |
| 12-Tone equal temperament | 900 |
| Just intonation | 884, 933, 906 |
In music from Western culture, a sixth is a musical interval encompassing six note letter names or staff positions (see Interval number for more details), and the major sixth is one of two commonly occurring sixths. It is qualified as major because it is the larger of the two. The major sixth spans nine semitones. Its smaller counterpart, the minor sixth, spans eight semitones. For example, the interval from C up to the nearest A is a major sixth. It is a sixth because it encompasses six note letter names (C, D, E, F, G, A) and six staff positions. It is a major sixth, not a minor sixth, because the note A lies nine semitones above C. Diminished and augmented sixths (such as C♯ to A♭ and C to A♯) span the same number of note letter names and staff positions, but consist of a different number of semitones (seven and ten, respectively).
The intervals from the tonic (keynote) in an upward direction to the second, to the third, to the sixth, and to the seventh scale degrees (of a major scale are called major.[2]
A commonly cited example of a melody featuring the major sixth as its opening is "My Bonnie Lies Over the Ocean".[3]
The major sixth is one of the consonances of common practice music, along with the unison, octave, perfect fifth, major and minor thirds, minor sixth, and (sometimes) the perfect fourth. In the common practice period, sixths were considered interesting and dynamic consonances along with their inverses the thirds. In medieval times theorists always described them as Pythagorean major sixths of 27/16 and therefore considered them dissonances unusable in a stable final sonority. How major sixths actually were sung in the Middle Ages is unknown. In just intonation, the (5/3) major sixth is classed as a consonance of the 5-limit.
A major sixth is also used in transposing music to E-flat instruments, like the alto clarinet, alto saxophone, E-flat tuba, trumpet, natural horn, and alto horn when in E-flat, as a written C sounds like E-flat on those instruments.
Assuming close-position voicings for the following examples, the major sixth occurs in a first inversion minor triad, a second inversion major triad, and either inversion of a diminished triad. It also occurs in the second and third inversions of a dominant seventh chord.
The septimal major sixth (12/7) is approximated in 53 tone equal temperament by an interval of 41 steps or 928 cents.
- ^ Jan Haluska, The Mathematical Theory of Tone Systems (New York: Marcel Dekker; London: Momenta; Bratislava: Ister Science, 2004), p.xxiii. ISBN 978-0-8247-4714-5. Septimal major sixth.
- ^ Bruce Benward and Marilyn Nadine Saker, Music: In Theory and Practice, Vol. I, seventh edition ([full citation needed] 2003): p. 52. ISBN 978-0-07-294262-0.
- ^ Blake Neely, Piano For Dummies, second edition (Hoboken, NJ: Wiley Publishers, 2009), p. 201. ISBN 978-0-470-49644-2.