- Augmented sixth
Infobox Interval
main_interval_name = augmented sixth
inverse =diminished third
complement =diminished third
other_names = -
abbreviation = aug6
semitones = 10
interval_class = 2
just_interval = 125:72| cents_equal_temperament = 1000
cents_just_intonation = 955An augmented sixth (Audio|Minor seventh on C.mid|Play) is one of three
musical interval s that span sixdiatonic scale degrees. The prefix 'augmented' identifies it as being the largest of the three intervals; the others being themajor sixth andminor sixth , which are one and twosemitone s smaller, respectively.Itsinversion is the diminished third, and itsenharmonic equivalent is theminor seventh ; Inseptimal meantone temperament , it is specifically equivalent to theharmonic seventh (a just interval of 7/4).In the tuning system known as
equal temperament the augmented sixth is equal to ten semitones and is a dissonant interval.The augmented sixth is relatively rare. Its most common occurrence is built on the lowered
submediant of the prevailing key, in which position the interval assumes a natural tendency to resolve by expanding to anoctave built on the dominant tonal degree. In its most common and expected resolution, the lower note of the interval moves downwards by aminor second to the dominant while the upper note, being chromatically inflected, is heard as the leading note of the dominant key, rising naturally by a minor second. It is the strong tendency to resolve in this way that properly identifies this interval as being an augmented sixth rather than its more common enharmonic equivalent: the minor seventh, which has a tendency to resolve inwardly.As the augmented sixth is correctly named only in certain specific contexts, the notational distinction between it and the identical sounding minor seventh is often ignored. Regardless of the true
diatonic context, many writers choose in favour of the more familiar minor seventh - especially in chord notation, in which chords containing it are always labelledseventh chord s.The augmented sixth interval in combination with certain other intervals forms the group of chords known collectively as
augmented sixth chord s.ee also
*
augmented sixth chord
*list of meantone intervals
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