Eleventh

This article is about an eleventh in music theory. For the character, see Eleventh Doctor. For the US constitution amendment, see Eleventh Amendment to the United States Constitution. For 11 July in Northern Ireland, see Eleventh night.

Perfect eleventh on C.

perfect eleventh

Inverse	perfect fifth
Name
Other names	Compound fourth
Abbreviation	P11
Size
Semitones	17
Interval class	1
Just interval	8:3
Cents
12-Tone equal temperament	1700.0
Just intonation	1698.0

Augmented eleventh on C.

augmented eleventh

Inverse	diminished fifth
Name
Abbreviation	A11
Size
Semitones	18
Interval class	6
Just interval	45:16
Cents
12-Tone equal temperament	1800.0
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.

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.

An eleventh chord is the stacking of five thirds in the span of an eleventh. In common practice tonality, the eleventh chord usually had subdominant function, occurring on the second degree (supertonic) of the major scale.

See also

• Eleventh chord
• Suspended chord