Eleventh

{{short description|Musical interval of ten diatonic steps}}

Image:Perfect eleventh on C.png

{{Infobox musical interval|

main_interval_name = perfect eleventh|

inverse = perfect fifth|

other_names = Compound fourth|

abbreviation = P11|

semitones = 17|

interval_class = 1|

just_interval = 8:3|

cents_equal_temperament = 1700.0|

cents_24T_equal_temperament = |

cents_just_intonation = 1698.0

}}

Image:Augmented eleventh on C.png

{{Infobox musical interval|

main_interval_name = augmented eleventh|

inverse = diminished fifth|

other_names = |

abbreviation = A11|

semitones = 18|

interval_class = 6|

just_interval = 45:16|

cents_equal_temperament = 1800.0|

cents_24T_equal_temperament = |

cents_just_intonation = 1790.2

}}

In music theory, an eleventh is a compound interval consisting of an octave plus a fourth.

A perfect eleventh spans 17 and the augmented eleventh 18 semitones, or 10 steps in a diatonic scale.

Since there are only seven degrees in a diatonic scale, the eleventh degree is the same as the subdominant (IV).{{cite book|last1=Benward|first1=Bruce|last2=Saker|first2=Marilyn|title=Music: In Theory and Practice, Vol. I|publisher=McGraw-Hill Education|date=2003|isbn=978-0-07-294262-0}} The eleventh is considered highly dissonant with the major third.

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.