In
music theory
Music theory is the study of theoretical frameworks for understanding the practices and possibilities of music. ''The Oxford Companion to Music'' describes three interrelated uses of the term "music theory": The first is the "Elements of music, ...
, an eleventh is a
compound interval consisting of an
octave
In music, an octave (: eighth) or perfect octave (sometimes called the diapason) is an interval between two notes, one having twice the frequency of vibration of the other. The octave relationship is a natural phenomenon that has been referr ...
plus a
fourth.
A perfect eleventh spans 17 and the augmented eleventh 18
semitones, or 10 steps in a
diatonic scale
In music theory a diatonic scale is a heptatonic scale, heptatonic (seven-note) scale that includes five whole steps (whole tones) and two half steps (semitones) in each octave, in which the two half steps are separated from each other by eith ...
.
Since there are only seven
degrees in a diatonic scale, the eleventh degree is the same as the
subdominant (IV).
The eleventh is considered highly
dissonant with the
major third
In music theory, a third is a Interval (music), musical interval encompassing three staff positions (see Interval (music)#Number, Interval number for more details), and the major third () is a third spanning four Semitone, half steps or two ...
.
An
eleventh chord is the stacking of five
thirds in the span of an eleventh. In
common practice tonality, it usually had subdominant
function as minor eleventh chord on the second degree (
supertonic) of the
major scale.
See also
*
Eleventh chord
*
Extended chord
References
Chord factors
Fourths (music)
Compound intervals
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