Superpyth: Difference between revisions

(5 intermediate revisions by 3 users not shown)

Line 130:

Perhaps a more interesting approach is for the tonic chords of superpyth to be considered the tetrad 1–7/6–4/3–3/2 ([[6:7:8:9]]) and its utonal inverse 1–9/8–9/7–3/2 (representing [[14:16:18:21]] as [[64/63]] is tempered out), the former of which is a subminor chord with added fourth, and the latter a supermajor chord with added second (resembling the {{w|mu chord}} of {{w|Steely Dan}} fame). Both of these have distinct moods, and are stable and consonant, if somewhat more sophisticated than their classic 5-limit counterparts. To this group we could also add 1–9/8–4/3–3/2 (a sus2-4 chord). These three chords comprise the three ways to divide the superpyth perfect fifth into two whole tones and one septimal minor third. In the diatonic major scale, the 1–7/6–4/3–3/2 chord occurs on II, III, and VI, while its inverse occurs on I, IV, and V. Compared to meantone, major and minor swap places in a sense, though in a different way from in [[mavila]]. [[Chromatic]] or [[enharmonic]] alterations of them also exist, for example, the 1–9/8–9/7–3/2 chord may be altered to 1–9/8–11/8–3/2 (8:9:11:12), which is impressive-sounding, resembling a sus4 but with even more tension; it resolves quite nicely to 1–9/8–9/7–3/2.

Another approach takes account of the fact that, in the 5-limit, the major triad can be constructed by octave-reducing odd harmonics 1, 3, and 5, giving us 4:5:6, with the minor triad being its utonal inversion. A similar construction of septimal chords gives us 1–7/6–4/3 ([[6:7:8]]) and its inversion 1–8/7–4/3 ([[21:24:28]]). These intervals contrast by [[49/48]], similarly to how 5-limit thirds contrast by [[25/24]]. There are some issues, however. For example, the 6:7:8 chord has the root on the top rather than the bottom, and the notes may clash from being too close to each other. However, the wide voicing of these chords, those being 1–7/4–3 (4:7:12) and 1–12/7–3 (7:12:21), solve both of these issues. These triads span a twelfth. In terms of the [[chain of fifths]], these chords are simpler in superpyth than the 5-limit triads in meantone.

Therefore, it may be helpful to also consider the [[9-odd-limit]] [[anomalous saturated suspension|saturated suspensions]], 1–7/6–3/2–7/4 ([[12:14:18:21]]) and 1–9/7–3/2–12/7 ([[14:18:21:24]]), which extend the chords above and are good for creating tensions and resolutions: 1–9/7–3/2–12/7 on the fifth degree creates a leading tone that wants to go to the tonic; 1–7/6–3/2–7/4 on the fourth degree creates a flat sixth that wants to go to the fifth.

In meantone, the dominant seventh chord, a tempering of [[20:25:30:36|1–5/4–3/2–9/5]], is often used on the dominant to resolve to the tonic. A similar chord in superpyth is [[28:36:42:49|1–9/7–3/2–7/4]], with a leading tone at 9/7 above the perfect fifth, or [[27/14]]. This chord contains a [[49/36]] [[tritone]] between the 9/7 and 7/4, which creates tension in the chord. (However, 11-limit superpyth maps it to [[15/11]], making it a [[15-odd-limit]] [[swetismic chords|swetismic essentially tempered chord]].)

== Scales ==

; 5-note mos ([[2L 3s]], proper)

In contrast to the meantone pentic scale, the superpyth pentic is much softer and mellow in quality, which is related to the fact that the intervals of the 2.3.7 subgroup cluster around [[5edo]]. As such, this system may be preferred over diatonic for interval classification, with 7/6 becoming a major interval and 8/7~9/8 becoming a minor one, and 49/48~[[28/27]] becoming a chroma. See [[Pentatonic Functional Just System]] for further ~~reading~~.

In contrast to the meantone pentic scale, the superpyth pentic is much softer and mellow in quality, which is related to the fact that the intervals of the 2.3.7 subgroup cluster around [[5edo]]. As such, this system may be preferred over diatonic for interval classification, with 7/6 becoming a major interval and 8/7~9/8 becoming a minor one, and 49/48~[[28/27]] becoming a chroma. See [[Pentatonic Functional Just System]] for a further explanation of what such a system would look like.

; 7-note mos ([[5L 2s]], improper)

Line 167:

Line 171:

A case can also be made for tuning archy even sharper than 27edo, which involves the notion of splitting the error of 4/3 into that of 8/7 and 7/6. This is a similar logic to Zarlino's preference for [[2/7-comma meantone]], treating [[~]][[6:7:8]] as the fundamental chord of the 2.3.7 subgroup, and in this case would imply 2/5-comma archy, where [[49/48]] is tuned justly, and 8/7 and 7/6 are both 1/5 a septimal comma off, and which is closely approximated by [[32edo]]. Unlike in the case of meantone, [[CEE]] optimization agrees with the notion of such a sharp tuning, where 3 is twice as sharp as 7. In this range, the best extension to prime 5 is ultrapyth.

Finally, it may be noted that the {{w|plastic ~~number~~}} has a value of ~486.822 cents, which, taken as a generator (~4/3) and assuming a pure-octave period, constitutes an extremely sharp variety of archy. ~~This can be explained since archy equates [[21/16]] and [[4/3]]~~, ~~making~~ the ~9:12:~~16:21 chord evenly spaced by ~4/3, and when keeping {{nowrap| ~9~~ + ~~~12 {{=}} ~21 }} the generator becomes the plastic number~~.

Finally, it may be noted that the {{w|plastic ratio}} has a value of ~486.822 cents, which, taken as a generator (~4/3) and assuming a pure-octave period, constitutes an extremely sharp variety of archy. In fact, it is the tuning that makes ~6:7:8 become +1+1 [[delta-rational]].

=== Norm-based tunings ===

@@ Line 130: / Line 130: @@
 Perhaps a more interesting approach is for the tonic chords of superpyth to be considered the tetrad 1–7/6–4/3–3/2 ([[6:7:8:9]]) and its utonal inverse 1–9/8–9/7–3/2 (representing [[14:16:18:21]] as [[64/63]] is tempered out), the former of which is a subminor chord with added fourth, and the latter a supermajor chord with added second (resembling the {{w|mu chord}} of {{w|Steely Dan}} fame). Both of these have distinct moods, and are stable and consonant, if somewhat more sophisticated than their classic 5-limit counterparts. To this group we could also add 1–9/8–4/3–3/2 (a sus2-4 chord). These three chords comprise the three ways to divide the superpyth perfect fifth into two whole tones and one septimal minor third. In the diatonic major scale, the 1–7/6–4/3–3/2 chord occurs on II, III, and VI, while its inverse occurs on I, IV, and V. Compared to meantone, major and minor swap places in a sense, though in a different way from in [[mavila]]. [[Chromatic]] or [[enharmonic]] alterations of them also exist, for example, the 1–9/8–9/7–3/2 chord may be altered to 1–9/8–11/8–3/2 (8:9:11:12), which is impressive-sounding, resembling a sus4 but with even more tension; it resolves quite nicely to 1–9/8–9/7–3/2.
 Another approach takes account of the fact that, in the 5-limit, the major triad can be constructed by octave-reducing odd harmonics 1, 3, and 5, giving us 4:5:6, with the minor triad being its utonal inversion. A similar construction of septimal chords gives us 1–7/6–4/3 ([[6:7:8]]) and its inversion 1–8/7–4/3 ([[21:24:28]]). These intervals contrast by [[49/48]], similarly to how 5-limit thirds contrast by [[25/24]]. There are some issues, however. For example, the 6:7:8 chord has the root on the top rather than the bottom, and the notes may clash from being too close to each other. However, the wide voicing of these chords, those being 1–7/4–3 (4:7:12) and 1–12/7–3 (7:12:21), solve both of these issues. These triads span a twelfth. In terms of the [[chain of fifths]], these chords are simpler in superpyth than the 5-limit triads in meantone.
+Therefore, it may be helpful to also consider the [[9-odd-limit]] [[anomalous saturated suspension|saturated suspensions]], 1–7/6–3/2–7/4 ([[12:14:18:21]]) and 1–9/7–3/2–12/7 ([[14:18:21:24]]), which extend the chords above and are good for creating tensions and resolutions: 1–9/7–3/2–12/7 on the fifth degree creates a leading tone that wants to go to the tonic; 1–7/6–3/2–7/4 on the fourth degree creates a flat sixth that wants to go to the fifth.
+In meantone, the dominant seventh chord, a tempering of [[20:25:30:36|1–5/4–3/2–9/5]], is often used on the dominant to resolve to the tonic. A similar chord in superpyth is [[28:36:42:49|1–9/7–3/2–7/4]], with a leading tone at 9/7 above the perfect fifth, or [[27/14]]. This chord contains a [[49/36]] [[tritone]] between the 9/7 and 7/4, which creates tension in the chord. (However, 11-limit superpyth maps it to [[15/11]], making it a [[15-odd-limit]] [[swetismic chords|swetismic essentially tempered chord]].)
 == Scales ==
 ; 5-note mos ([[2L&nbsp;3s]], proper)
-In contrast to the meantone pentic scale, the superpyth pentic is much softer and mellow in quality, which is related to the fact that the intervals of the 2.3.7 subgroup cluster around [[5edo]]. As such, this system may be preferred over diatonic for interval classification, with 7/6 becoming a major interval and 8/7~9/8 becoming a minor one, and 49/48~[[28/27]] becoming a chroma. See [[Pentatonic Functional Just System]] for further reading.
+In contrast to the meantone pentic scale, the superpyth pentic is much softer and mellow in quality, which is related to the fact that the intervals of the 2.3.7 subgroup cluster around [[5edo]]. As such, this system may be preferred over diatonic for interval classification, with 7/6 becoming a major interval and 8/7~9/8 becoming a minor one, and 49/48~[[28/27]] becoming a chroma. See [[Pentatonic Functional Just System]] for a further explanation of what such a system would look like.
 ; 7-note mos ([[5L&nbsp;2s]], improper)
@@ Line 167: / Line 171: @@
 A case can also be made for tuning archy even sharper than 27edo, which involves the notion of splitting the error of 4/3 into that of 8/7 and 7/6. This is a similar logic to Zarlino's preference for [[2/7-comma meantone]], treating [[~]][[6:7:8]] as the fundamental chord of the 2.3.7 subgroup, and in this case would imply 2/5-comma archy, where [[49/48]] is tuned justly, and 8/7 and 7/6 are both 1/5 a septimal comma off, and which is closely approximated by [[32edo]]. Unlike in the case of meantone, [[CEE]] optimization agrees with the notion of such a sharp tuning, where 3 is twice as sharp as 7. In this range, the best extension to prime 5 is ultrapyth.
-Finally, it may be noted that the {{w|plastic number}} has a value of ~486.822 cents, which, taken as a generator (~4/3) and assuming a pure-octave period, constitutes an extremely sharp variety of archy. This can be explained since archy equates [[21/16]] and [[4/3]], making the ~9:12:16:21 chord evenly spaced by ~4/3, and when keeping {{nowrap| ~9 + ~12 {{=}} ~21 }} the generator becomes the plastic number.
+Finally, it may be noted that the {{w|plastic ratio}} has a value of ~486.822 cents, which, taken as a generator (~4/3) and assuming a pure-octave period, constitutes an extremely sharp variety of archy. In fact, it is the tuning that makes ~6:7:8 become +1+1 [[delta-rational]].
 === Norm-based tunings ===