20:25:30:36: Difference between revisions

20:25:30:36, a major-minor seventh chord, is a tetrad in 5-limit harmony, sometimes considered a form of dominant seventh chord. It combines a 5/4 major third with the consonant 9/5 seventh that would be found in a Ptolemaic minor seventh chord on the same root, creating a 36/25 tritone between the two.

The major-minor seventh chord is found rooted at the I (1⁄1) and IV (4⁄3) of the duodene.

In septimal meantone, the 36/25 tritone is equated with the more consonant interval 10/7, and the major-minor seventh chord becomes an essentially tempered chord in the 9-odd-limit.

@@ Line 1: / Line 1: @@
-{{Infobox Chord|20:25:30:36|Name = Major-minor seventh}}
+{{Infobox Chord|20:25:30:36}}
-'''20:25:30:36''' (1⁄1–5⁄4–3⁄2–9⁄5), a '''major-minor seventh chord''', is a [[tetrad]] in [[5-limit]] harmony, sometimes considered a form of [[dominant seventh chord]]. It combines a [[5/4]] major third with the [[consonant]] [[9/5]] seventh that would be found in a [[Ptolemaic minor seventh chord]] on the same root, creating a [[36/25]] tritone between the two.
+'''20:25:30:36''', a ''major-minor seventh chord'', is a [[tetrad]] in [[5-limit]] harmony, sometimes considered a form of [[dominant seventh chord]]. It combines a [[5/4]] major third with the [[consonant]] [[9/5]] seventh that would be found in a [[Ptolemaic minor seventh chord]] on the same root, creating a [[36/25]] tritone between the two.
-The major-minor seventh chord is found rooted at 1⁄1 (I) and 4⁄3 (IV) in the [[duodene]].
+The major-minor seventh chord is found rooted at the I ({{Frac|1|1}}) and IV ({{Frac|4|3}}) of the [[duodene]].
 In [[Meantone_family#Septimal_meantone|septimal meantone]], the 36/25 tritone is equated with the more consonant interval [[10/7]], and the major-minor seventh chord becomes an [[essentially tempered chord]] in the [[9-odd-limit]].

Revision as of 18:45, 12 August 2024