Ploidacot/Diploid dicot

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Diploid dicot
Pergen [P8/2, P4/2]
Numeral form 2-ploid 2-cot
Pure generator size 249.02 ¢
Pure period size 600 ¢
Forms 6, 10, 14, 24
Characteristic multival entry 4

Diploid dicot is a temperament archetype where the generator is a neutral third, two of which stack to a 3/2 perfect fifth, and the period is half a 2/1 octave, or 600 ¢. In other words, this is the same as the hemipythagorean structure. The generator can also be characterized as an inframinor third or ultramajor second, two of which reach a perfect fourth. Diploid dicot temperaments usually generate the decatonic scale 4L 6s and the 14-note scale 10L 4s.

Intervals and notation

Diploid dicot 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 dicot intervals align with standard dicot intervals (which use neutral chain-of-fifths notation).

Diploid dicot intervals (assuming pure fifth and octave)
# Ploid 1 Ploid 2
Cents Notation Name Cents Notation Name
−7 543.157 1143.157 Cd semidiminished octave
−6 294.135 Eb minor third 894.135
−5 45.112 645.112 Gd semidiminished fifth
−4 396.090 996.090 Bb minor seventh
−3 147.067 Dd neutral second 747.067
−2 498.045 F perfect fourth 1098.045
−1 249.022 849.022 Ad neutral sixth
0 0 C perfect unison 600
1 350.978 Ed neutral third 950.978
2 101.955 701.955 G perfect fifth
3 452.933 1052.933 Bd neutral seventh
4 203.910 D major second 803.910
5 554.888 Ft semiaugmented fourth 1154.888
6 305.865 905.865 A major sixth
7 56.843 Ct semiaugmented unison 656.843

Temperament interpretations

A diploid dicot temperament must temper out at least two commas: one to equate an interval to its octave-complement, and one to equate another interval to its fifth-complement. As a result, diploid dicot temperaments must be at least in the 7-limit or another 4-prime subgroup. As such, there are few specifically defined interpretations of diploid dicot as a temperament, and instead they may be found by combining dicot and diploid monocot temperaments.