In Western
tonal music theory
Music theory is the study of theoretical frameworks for understanding the practices and possibilities of music. ''The Oxford Companion to Music'' describes three interrelated uses of the term "music theory": The first is the "Elements of music, ...
, an augmented octave is the sum of a perfect
octave
In music, an octave (: eighth) or perfect octave (sometimes called the diapason) is an interval between two notes, one having twice the frequency of vibration of the other. The octave relationship is a natural phenomenon that has been referr ...
and an
augmented unison
In modern Western tonality, tonal music theory an augmented unison or augmented prime is the interval (music), interval between two notes on the same staff position, or denoted by the same note letter, whose alterations cause them, in ordinary eq ...
or chromatic semitone. It is the
interval between two notes, with the same note letter on staff positions an octave apart, whose alterations cause them, in ordinary
equal temperament
An equal temperament is a musical temperament or Musical tuning#Tuning systems, tuning system that approximates Just intonation, just intervals by dividing an octave (or other interval) into steps such that the ratio of the frequency, frequencie ...
, to be thirteen
semitones apart. In other words, it is a perfect
octave
In music, an octave (: eighth) or perfect octave (sometimes called the diapason) is an interval between two notes, one having twice the frequency of vibration of the other. The octave relationship is a natural phenomenon that has been referr ...
which has been widened by a half-step, such as B and B or C and C; it is a compound augmented unison. It is the
enharmonic
In music, two written notes have enharmonic equivalence if they produce the same pitch but are notated differently. Similarly, written intervals, chords, or key signatures are considered enharmonic if they represent identical pitches that ar ...
equivalent of a
minor ninth
In music, a ninth is a compound interval consisting of an octave plus a second.
Like the second, the interval of a ninth is classified as a dissonance in common practice tonality. Since a ninth is an octave larger than a second, its ...
.
[
]
See also
* False relation
* List of musical intervals
* List of pitch intervals
*
References
Augmented intervals
Octaves
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