In classical music from Western culture, a diminished fourth (
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A diminished fourth is enharmonically equivalent to a major third; that is, it spans the same number of semitones, and they are physically the same pitch in twelve-tone equal temperament. For example, B–D♯ is a major third; but if the same pitches are spelled B and E♭, as occurs in the C harmonic minor scale, the interval is instead a diminished fourth. In other tunings, however, they are not necessarily identical. For example, in 31 equal temperament the diminished fourth is slightly wider than a major third, and is instead the same width as the septimal major third.
The 32:25 just diminished fourth arises in the C harmonic minor scale between B and E♭.[5]
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[edit] Sources
- ^ a b Benward & Saker (2003). Music: In Theory and Practice, Vol. I, p.54. ISBN 978-0-07-294262-0. Specific example of an d4 not given but general example of perfect intervals described.
- ^ Haluska, Jan (2003). The Mathematical Theory of Tone Systems, p.xxv. ISBN 0824747143. Classic diminished fourth.
- ^ Hoffmann, F.A. (1881). Music: Its Theory & Practice, p.89-90. Thurgate & Sons. Digitized Aug 16, 2007.
- ^ Benward & Saker (2003), p.92.
- ^ Paul, Oscar (1885). A manual of harmony for use in music-schools and seminaries and for self-instruction, p.165. Theodore Baker, trans. G. Schirmer.
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Numbers in brackets are the number of semitones in the interval.
Fractional semitones are approximate.
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Twelve-semitone
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Perfect
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Major
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Minor
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Augmented
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Diminished
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Compound
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| Other systems |
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Supermajor
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Neutral
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Subminor
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| Other intervals |
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Groups
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Measurement
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Others
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