View source for Eleventh

{{short description|Musical interval of ten diatonic steps}}
[[Image:Perfect eleventh on C.png|thumb|Perfect eleventh on C. {{Audio|Perfect eleventh on C.mid|Play}}]]
{{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|thumb|Augmented eleventh on C. {{Audio|Augmented eleventh on C.mid|Play}}]]
{{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 [[Interval (music)#Simple and compound|compound interval]] consisting of an [[octave]] plus a [[Perfect fourth|fourth]].

A '''perfect eleventh''' spans 17 and the '''augmented eleventh''' 18 [[semitone]]s, or 10 steps in a [[diatonic scale]].

Since there are only seven [[scale degree|degrees]] in a diatonic scale, the eleventh degree is the same as the [[subdominant]] (IV).<ref>{{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}}</ref> The eleventh is considered highly [[Consonance and dissonance|dissonant]] with the [[major third]].

An [[eleventh chord]] is the stacking of five [[List of third intervals|thirds]] in the span of an eleventh. In [[common practice period|common practice]] [[tonality]], it usually had subdominant [[Function (music)|function]] as minor eleventh chord on the second degree ([[supertonic]]) of the [[major scale]].

The [[quarter tone]] scale offers an alternative eleventh of 1650 cents, which is very close to the just interval 11:4, the undecimal eleventh (1651.3 cents).

==See also==
*[[Eleventh chord]]
*[[Extended chord]]

==References==
{{reflist}}

{{Intervals}}
{{Chord factors}}

[[Category:Chord factors]]
[[Category:Fourths (music)]]
[[Category:Compound intervals]]

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