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{{Infobox ET}} | |||
{{ED intro}} It is best known as the equal-tempered version of the [[Bohlen–Pierce]] scale, and therefore has received by far the most attention among equal divisions of the tritave. | |||
[[File:13edt.png|thumb|alt=13edt.png|A plot of the [[Riemann zeta function#Removing primes|no-twos Z-function]], in terms of which 13edt is the fourth no-twos zeta peak [[EDT]].]] | |||
[[File:pts-3-5-7-e3-twtop.jpg|thumb|Projective tuning space of the [[3.5.7 subgroup]], showing 13edt near the center.]] | |||
== Theory == | |||
{{See also| Relationship between Bohlen-Pierce and octave-ful temperaments }} | |||
[[ | 13edt provides an excellent approximation to the [[3.5.7 subgroup]], especially for its size, being comparable to [[34edo]]'s accuracy in the 5-limit. In this subgroup, it tempers out [[245/243]] and [[3125/3087]], the same commas as the rank-2 [[bohpier]] temperament. It is less impressive in higher prime limits, but makes for excellent no-twos 7-limit harmony. For higher limits, the multiples of 13 ([[26edt]], [[39edt]], and [[52edt]]) come to the fore. | ||
13edt can be described as approximately 8.202[[edo]]. This implies that each step of 13edt can be approximated by 5 steps of [[41edo]]. | |||
{| class="wikitable" | In the 3.5.7 subgroup, 13edt maintains the smallest relative error of any EDT until [[258edt]] and [[271edt]], and the smallest absolute error until [[56edt]]. | ||
=== Odd harmonics === | |||
{{Harmonics in equal|13|3|1|prec=2|intervals=odd|columns=11}} | |||
{{Harmonics in equal|13|3|1|prec=2|intervals=odd|columns=12|start=12|collapsed=true|title=Approximation of odd harmonics in 13edt (continued)}} | |||
== Intervals == | |||
{{Main|Intervals of BP}} | |||
{| class="wikitable center-all right-2 right-3" | |||
|- | |||
! Steps | |||
! [[Cent]]s | |||
! [[Hekt]]s | |||
! [[4L 5s (3/1-equivalent)|Enneatonic]]<br />degree | |||
! Corresponding<br />3.5.7 subgroup<br />intervals | |||
! [[Lambda ups and downs notation|Lambda]]<br />(sLsLsLsLs, {{nowrap|E {{=}} 1/1}}) | |||
|- | |- | ||
| 0 | |||
| 0 | |||
| 0 | |||
| P1 | |||
| 1/1 | |||
| E | |||
|- | |- | ||
| 1 | |||
| 146.3 | |||
| | A1/m2 | | 100 | ||
| | | A1/m2 | ||
| | | [[49/45]] (−1.1{{c}}); [[27/25]] (+13.1{{c}}) | ||
| F | |||
|- | |- | ||
| 2 | |||
| 292.6 | |||
| | M2/d3 | | 200 | ||
| | | M2/d3 | ||
| | | [[25/21]] (−9.2{{c}}) | ||
| F#, Gb | |||
|- | |- | ||
| 3 | |||
| 438.9 | |||
| | A2/P3/d4 | | 300 | ||
| | | A2/P3/d4 | ||
| | | [[9/7]] (+3.8{{c}}) | ||
| G | |||
|- | |- | ||
| 4 | |||
| 585.2 | |||
| | A3/m4/d5 | | 400 | ||
| | | A3/m4/d5 | ||
| | | [[7/5]] (+2.7{{c}}) | ||
| H | |||
|- | |- | ||
| 5 | |||
| 731.5 | |||
| | M4/m5 | | 500 | ||
| | | M4/m5 | ||
| | | [[75/49]] (−5.4{{c}}) | ||
| H#, Jb | |||
|- | |- | ||
| 6 | |||
| 877.8 | |||
| | A4/M5 | | 600 | ||
| | | A4/M5 | ||
| | | [[5/3]] (−6.5{{c}}) | ||
| J | |||
|- | |- | ||
| 7 | |||
| 1024.1 | |||
| | A5/m6/d7 | | 700 | ||
| | | A5/m6/d7 | ||
| | | [[9/5]] (+6.5{{c}}) | ||
| A | |||
|- | |- | ||
| 8 | |||
| 1170.4 | |||
| | M6/m7 | | 800 | ||
| | | M6/m7 | ||
| | | [[49/25]] (+5.4{{c}}) | ||
| A#, Bb | |||
|- | |- | ||
| 9 | |||
| 1316.7 | |||
| | A6/M7/d8 | | 900 | ||
| | | A6/M7/d8 | ||
| | | [[15/7]] (−2.7{{c}}) | ||
| B | |||
|- | |- | ||
| 10 | |||
| 1463.0 | |||
| | P8/d9 | | 1000 | ||
| | | P8/d9 | ||
| | | [[7/3]] (−3.8{{c}}) | ||
| C | |||
|- | |- | ||
| 11 | |||
| 1609.3 | |||
| | A8/m9 | | 1100 | ||
| | | A8/m9 | ||
| | | [[63/25]] (+9.2{{c}}) | ||
| C#, Db | |||
|- | |- | ||
| 12 | |||
| 1755.7 | |||
| | M9/d10 | | 1200 | ||
| | | M9/d10 | ||
| [[135/49]] (+1.1{{c}}); [[25/9]] (−13.1{{c}}) | |||
| | | D | ||
|- | |- | ||
| 13 | |||
| 1902.0 | |||
| | A9/P10 | | 1300 | ||
| | | A9/P10 | ||
| | | [[3/1]] | ||
| E | |||
|} | |} | ||
== | == JI approximation == | ||
< | [[File:13ed3-17-001.svg|alt=alt : Your browser has no SVG support.]] | ||
[[Category: | |||
[[Category: | == Regular temperament properties == | ||
{| class="wikitable center-4 center-5 center-6" | |||
! rowspan="2" | Subgroup | |||
! rowspan="2" | [[Comma list]] | |||
! rowspan="2" | [[Mapping]] | |||
! rowspan="2" | Optimal<br>Equave stretch (¢) | |||
! colspan="2" | Tuning error | |||
|- | |||
! [[TE error|Absolute]] (¢) | |||
! [[TE simple badness|Relative]] (%) | |||
|- | |||
| 3.5.7 | |||
| 245/243, 3125/3087 | |||
| [{{val| 13 19 23 }}] (b13) | |||
| +1.393 | |||
| 1.150 | |||
| 0.79 | |||
|} | |||
=== Rank-2 temperaments === | |||
{| class="wikitable center-all right-3 left-5" | |||
|+ style="font-size: 105%;" | Table of rank-2 temperaments by generator | |||
|- | |||
! Periods<br />per tritave | |||
! Generator<br />(reduced) | |||
! Cents<br />(reduced) | |||
! Associated<br />ratio | |||
! Temperament | |||
|- | |||
| 1 | |||
| 1\13 | |||
| 146.30 | |||
| 49/45 | |||
| [[Procyon]] | |||
|- | |||
| 1 | |||
| 2\13 | |||
| 292.61 | |||
| 25/21 | |||
| [[Sirius]] | |||
|- | |||
| 1 | |||
| 3\13 | |||
| 438.91 | |||
| 9/7 | |||
| [[BPS]] | |||
|- | |||
| 1 | |||
| 4\13 | |||
| 585.22 | |||
| 7/5 | |||
| [[Canopus]] | |||
|- | |||
| 1 | |||
| 5\13 | |||
| 731.63 | |||
| 75/49 | |||
| | |||
|- | |||
| 1 | |||
| 6\13 | |||
| 877.83 | |||
| 5/3 | |||
| [[Arcturus]] | |||
|} | |||
== Music == | |||
See also: [[Bohlen–Pierce scale/Music]] | |||
; [[Bryan Deister]] | |||
* [https://www.youtube.com/shorts/dKFwJsxE3VU ''13ed3''] (2026) | |||
== See also == | |||
* [[Bohlen-p_et]] | |||
* [[Catalog of 3.5.7 subgroup rank two temperaments]] | |||
* [[No-twos subgroup temperaments#3.5.7 subgroup temperaments]] | |||
* [[19ed5|19ED5]]: relative ED5 | |||
* [[23ed7|23ED7]]: relative ED7 | |||
[[Category:Tritave]] | |||
[[Category:Macrotonal]] | |||
[[Category:Nonoctave]] | |||
[[Category:Bohlen–Pierce]] | |||