Magic: Difference between revisions

→Interval chain: modernize the table
→Chords and harmony: rework with consideration on the "fundamental otonal consonance"
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== Chords and harmony ==
== Chords and harmony ==
=== List of chords ===
{{Main| Chords of magic }}
{{Main| Chords of magic }}
{{See also| Magic Tetrachords }}
=== Functional harmony ===
{{See also| Functional harmony in rank-2 temperaments }}
{{See also| Functional harmony in rank-2 temperaments }}


In terms of generator steps, the just major triad (1–5/4–3/2) and just minor triad (1–6/5–3/2) are 0–1–5 and 0–4–5; this is similar, but also in clear contrast to the 0-4-1 and 0-(−3)-1 of [[meantone]]. Two approaches to functional harmony thus arise.  
The fundamental otonal consonance of magic, voiced in a roughly {{w|tertian harmony|tertian}} manner, is 4:5:6:7:9, available in a 13-tone mos. To start with, consider the the just major triad (1–5/4–3/2) and just minor triad (1–6/5–3/2). In terms of generator steps, they are 0–1–5 and 0–4–5; this is similar, but also in clear contrast to the 0–4–1 and 0–(−3)–1 of [[meantone]]. Two approaches to functional harmony thus arise.  


First, we suggest using the triads above as the basis of harmony, but swapping the roles of 3 and 5 according to their temperamental complexities (number of generator steps). Thus a "dominant" chord is 5/4 over tonic; a "subdominant" chord is 5/4 under tonic. This leads to an approach closely adherent to mos scales. The 7-tone mos contains a tonic and a "dominant" chord. The 10-tone mos is good for encapsulating tonic, "pre-dominant", and "dominant" functions. We also have the augmented triad (1–5/4–14/9) as the magic analog of the suspended chord of meantone.  
First, we can use the triads above as the basis of harmony, but swapping the roles of 3 and 5 according to their temperamental complexities (number of generator steps). Thus a "dominant" chord is 5/4 over tonic; a "subdominant" chord is 5/4 under tonic. This leads to an approach closely adherent to mos scales. The 7-tone mos contains a tonic and a "dominant" chord. The 10-tone mos is good for encapsulating tonic, "pre-dominant", and "dominant" functions. The suspended chord of meantone is made of two generators stacked, and doing the same in magic, we also have the augmented triad (1–5/4–14/9) as the magic analog of the suspended chord of meantone.  


Second, we suggest using the same triads as the basis of harmony, and keeping the roles of 3 and 5 as in meantone. This means dominant is still 3/2 over tonic, for example. A consequence is we must step out of the logic of mos scales, as they are often too restrictive without the many fifths to stack. Try starting unlimited and thinking directly about ratios and comma pumps. You might end up with a diatonic-like scale with comma-level inflections here and there, but it is also possible to slap whatever scale you like, using inflections to reach the ratios.
Second, we can use the same triads as the basis of harmony, and keeping the role of the [[chain of fifths]] as the spine on which the functions are defined. This means dominant is still 3/2 over tonic, for example. A consequence is we must step out of the logic of mos scales, as they are often too restrictive without the many fifths to stack. This is essentially working in JI, but using the commas tempered out in some way to lock into the identity of the temperament.


== Scales ==
== Scales ==