Acoustic pi: Difference between revisions

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|30edπ
|30edπ
|Close to [[18edo]], but sets fractional temperaments to 4:5:6 triad.
|Close to [[18edo]], but sets fractional temperaments to 4:5:6 triad.
|-
|38edπ
|Very close to [[23edo]]
|-
|71edπ
|Very close to [[43edo]]
|-
|109edπ
|Extremely close to [[66edo]]
|}
|}



Revision as of 12:21, 6 March 2023

Interval information
Expression [math]\displaystyle{ \pi }[/math]
Size in cents 1981.795¢
Name pitave
English Wikipedia has an article on:

Pi, the ratio of a circle's circumference to its octave, is equal to about 3.14159. When used as an equivalence interval, it becomes a rather minor thirteenth of 1981.795 cents.

Intervals that are close to it are 3/1, 22/7, and 355/113.

Equal divisions

Using 3.14159.../1 as an interval of equivalence results in an interesting nonoctave tuning.

EDπ-ED2 correspondence
N Description
2edπ A stack of two minor sevenths, represents a problem of squaring the circle
3edπ A stack of three compressed fifths, vaguely equivalent to 2edo
4edπ Close to equal multiplication of 4/3
5edπ Close to equal multiplication of 5/4, 3edo
6edπ Close to equal multiplication of 6/5, 4edo
20edπ Close to 12edo.
30edπ Close to 18edo, but sets fractional temperaments to 4:5:6 triad.
38edπ Very close to 23edo
71edπ Very close to 43edo
109edπ Extremely close to 66edo

Temperaments of interest

Engineer's temperament, tempering out π/3, the engineer's comma.

20edπ can be used to set 3:4:5 triad with a fractional-octave temperament just as 12edo does with the 4:5:6 triad.