Ploidacot/Diploid monocot: Difference between revisions

From Xenharmonic Wiki
Jump to navigation Jump to search
Xenllium (talk | contribs)
No edit summary
Tags: Mobile edit Mobile web edit
Xenllium (talk | contribs)
No edit summary
Tags: Mobile edit Mobile web edit
Line 1: Line 1:
{{Breadcrumb}}{{Infobox ploidacot|Ploids=2|Shears=0|Cots=1|Pergen=[P8/2, P5]|Forms=8, 10, 12|Title=Diploid monocot|Wedgie=2}}
{{Breadcrumb}}{{Infobox ploidacot|Ploids=2|Shears=0|Cots=1|Pergen=[P8/2, P5]|Forms=10, 12, 22|Title=Diploid monocot|Wedgie=2}}
'''Diploid monocot''' is a temperament archetype where the generator is a [[3/2]] perfect fifth and the period is half a [[2/1]] octave, or 600{{c}}. The generator can also be characterized as a perfect fourth [[4/3]], or as a "perfect semitone" <math>\frac{3}{2\sqrt{2}}</math>. Diploid monocot temperaments usually generate the [[2L&nbsp;8s]] MOS structure and either [[2L&nbsp;10s]] (and thus [[12L&nbsp;2s]]) or [[10L&nbsp;2s]] as children.
'''Diploid monocot''' is a temperament archetype where the generator is a [[3/2]] perfect fifth and the period is half a [[2/1]] octave, or 600{{c}}. The generator can also be characterized as a perfect fourth [[4/3]], or as a "perfect semitone" <math>\frac{3}{2\sqrt{2}}</math>. Diploid monocot temperaments usually generate the [[2L&nbsp;8s]] MOS structure and either [[2L&nbsp;10s]] (and thus [[12L&nbsp;2s]]) or [[10L&nbsp;2s]] as children.


== Notation ==
== Intervals and notation ==
Diploid monocot notation is complicated as it conventionally requires either the introduction of new "[[hemipythagorean]]" ordinals or the use of scales other than the standard diatonic scale. As such, there is no universally accepted convention. Note and interval names are provided where diploid monocot intervals align with standard monocot intervals.
Diploid monocot notation is complicated as it conventionally requires either the introduction of new "[[hemipythagorean]]" ordinals or the use of scales other than the standard diatonic scale. As such, there is no universally accepted convention. Note and interval names are provided where diploid monocot intervals align with standard monocot intervals.


Line 18: Line 18:
! Notation
! Notation
! Name
! Name
|-
| −6
| 588.27
| Gb
| diminished fifth
| 1188.27
| —
| —
|-
|-
| −5
| −5
Line 106: Line 114:
| B
| B
| major seventh
| major seventh
|-
| 6
| 11.73
| —
| —
| 611.73
| F#
| augmented fourth
|}
|}



Revision as of 22:23, 5 January 2026

Diploid monocot
Pergen [P8/2, P5]
Numeral form 2-ploid 1-cot
Pure generator size 101.96 ¢
Pure period size 600 ¢
Forms 10, 12, 22
Characteristic multival entry 2

Diploid monocot is a temperament archetype where the generator is a 3/2 perfect fifth and the period is half a 2/1 octave, or 600 ¢. The generator can also be characterized as a perfect fourth 4/3, or as a "perfect semitone" [math]\displaystyle{ \frac{3}{2\sqrt{2}} }[/math]. Diploid monocot temperaments usually generate the 2L 8s MOS structure and either 2L 10s (and thus 12L 2s) or 10L 2s as children.

Intervals and notation

Diploid monocot notation is complicated as it conventionally requires either the introduction of new "hemipythagorean" ordinals or the use of scales other than the standard diatonic scale. As such, there is no universally accepted convention. Note and interval names are provided where diploid monocot intervals align with standard monocot intervals.

Diploid monocot intervals (assuming pure fifth and octave)
# Ploid 1 Ploid 2
Cents Notation Name Cents Notation Name
−6 588.27 Gb diminished fifth 1188.27
−5 90.22 Db minor second 690.22
−4 192.18 792.18 Ab minor sixth
−3 294.13 Eb minor third 894.13
−2 396.09 996.09 Bb minor seventh
−1 498.04 F perfect fourth 1098.04
0 0 C unison 600
1 101.96 701.96 G perfect fifth
2 203.91 D major second 803.91
3 305.87 905.87 A major sixth
4 407.82 E major third 1007.82
5 509.78 1109.78 B major seventh
6 11.73 611.73 F# augmented fourth

Temperament interpretations

By definition, diploid monocot temperaments equate some interval to its octave complement.

Diaschismic

Diaschismic sets 3/2 equal to 16/15 plus a semioctave, setting the semioctave equal to 45/32~64/45, and mapping 5/4 to 2 generators down. Diaschismic naturally extends to prime 17 by setting the flat 16/15 generator also equal to 17/16. Diaschismic is tuned best with fifths slightly sharp of just.

To extend to the 7-limit, a simple mapping (pajara) sets 7/5 equal to the semioctave, meaning 7/4 is a semioctave above 5/4. This suggests tuning the generator to about 709 ¢ (or equivalently 109 ¢). With a slightly less sharp fifth, septimal diaschismic maps 7/4 to 8 generators down.

Injera

Injera extends meantone by setting 7/5 equal to 10/7, so that both 5/4 and 7/4 are found at 4 generators up, offset by a 600 ¢ tritone representing both 7/5 and 10/7.