Diminished sixth

Diminished sixth

Inverse	augmented third
Name
Other names	-
Abbreviation	d6
Size
Semitones	7
Interval class	5
Just interval	192:125, 32:21,49:32
Cents
12-Tone equal temperament	700
24-Tone equal temperament	700
Just intonation	743

In classical music from Western culture, a diminished sixth () is an interval produced by narrowing a minor sixth by a chromatic semitone. For example, the interval from A to F is a minor sixth, eight semitones wide, and both the intervals from A♯ to F, and from A to F♭ are diminished sixths, spanning seven semitones.

<score sound>

{ \override Score.TimeSignature

1. 'stencil = ##f

   \relative c {
       \time 4/4
       \set Score.tempoHideNote = ##t \tempo 1 = 20
       <ais f'>1 <a? fes'>
   }

} </score>

Being diminished, it is considered a dissonant interval, despite being equivalent to an interval known for its consonance. Its inversion is the augmented third, and its enharmonic equivalent is the perfect fifth.

"Wolf fifth"

A severely dissonant diminished sixth is observed when a fixed-pitch instrument limited to twelve notes per octave is tuned using Pythagorean tuning or a meantone temperament with a fifth flatter than 700 cents. Typically, this is the interval between G♯ and E♭. Since this interval was considered to "howl like a wolf" (because of the beating), and since it sounded like a badly out-of-tune fifth, this interval is called the "wolf" fifth. A justly tuned fifth is the most consonant interval after the perfect unison and the perfect octave.