Augmented third

{{Infobox Interval|

main_interval_name = Augmented third|

inverse = diminished sixth|

complement = diminished sixth|

other_names = -|

abbreviation = A3|

semitones = 5|

interval_class = 5|

just_interval = 125:96,Haluska, Jan (2003). The Mathematical Theory of Tone Systems, p.xxvi. {{ISBN|0-8247-4714-3}}. Classic augmented third. 21:16, 64:49|

cents_equal_temperament = 500|

cents_24T_equal_temperament = 500|

cents_just_intonation = 457

}}

File:Augmented third on C.png

In classical music from Western culture, an augmented third ({{audio|Fourth_ET.ogg|Play}}) is an interval of five semitones. It may be produced by widening a major third by a chromatic semitone.Benward & Saker (2003). Music: In Theory and Practice, Vol. I, p.54. {{ISBN|978-0-07-294262-0}}.Hoffmann, F.A. (1881). Music: Its Theory & Practice, p.89-90. Thurgate & Sons. Digitized Aug 16, 2007. Archaically: superfluous third. For instance, the interval from C to E is a major third, four semitones wide, and both the intervals from C{{Music|b}} to E, and from C to E{{Music|sharp}} are augmented thirds, spanning five semitones. Being augmented, it is considered a dissonant interval.Benward & Saker (2003), p.92.

Its inversion is the diminished sixth, and its enharmonic equivalent is the perfect fourth.

The just augmented third, E{{music|#}}, is 456.99 cents or 125:96. {{audio|Just augmented third on C.mid|Play}} The Pythagorean augmented third, E{{music|#}}{{music|plus}}{{music|plus}}{{music|plus}}, is 521.51 cents or 177147:131072, eleven just perfect fifths. {{audio|Pythagorean augmented third on C.mid|Play}}