In music from
Western culture
Western culture, also known as Western civilization, European civilization, Occidental culture, Western society, or simply the West, refers to the Cultural heritage, internally diverse culture of the Western world. The term "Western" encompas ...
, a diminished octave () is an
interval produced by
narrowing a
perfect octave
In music, an octave (: eighth) or perfect octave (sometimes called the Pythagorean interval, diapason) is an Interval (music), interval between two notes, one having twice the frequency of vibration of the other. The octave relationship is a na ...
by a
chromatic semitone.
[Benward & Saker (2003). ''Music: In Theory and Practice, Vol. I'', p.54. . Specific example of an d8 not given but general example of perfect intervals described.] As such, the two notes are denoted by the same letter but have different
accidentals. For instance, the interval from C
4 to C
5 is a perfect octave, twelve semitones wide, and both the intervals from C
4 to C
5 and from C
4 to C
5 are diminished octaves, spanning eleven semitones. Being diminished, it is considered a
dissonant interval.
[Benward & Saker (2003), p.92.]
The diminished octave is
enharmonically equivalent to the
major seventh
In music from Western culture, a seventh is a interval (music), musical interval encompassing seven staff positions (see Interval (music)#Number, Interval number for more details), and the major seventh is one of two commonly occurring sevenths. ...
.
References
Diminished intervals
Octaves
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