171edo: Difference between revisions

m Text replacement - "Octave-reduced form, reduced to the first half-octave, and minimal form in parentheses if distinct" to "Octave-reduced form, reduced to the first half-octave, and minimal form in parentheses if distinct"
 
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Remarkable 5-limit commas 171et [[tempering out|tempers out]] are 32805/32768 ([[schisma]]), {{monzo| 1 -27 18 }} ([[ennealimma]]), {{monzo| -14 -19 19 }} ([[enneadeca]]), and {{monzo| -29 -11 20 }} ([[gammic comma]]), and remarkable 7-limit commas 171et tempers out are 2401/2400 ([[breedsma]]), 4375/4374 ([[ragisma]]), 65625/65536 ([[horwell comma]]), 250047/250000 ([[landscape comma]]), 420175/419904 ([[wizma]]), and 703125/702464 ([[meter]]). Therefore, 171et [[support]]s a number of notable 7-limit rank-2 temperaments: [[pontiac]], [[sesquiquartififths]], [[term]], [[ennealimmal]], [[tertiaseptal]], [[supermajor (temperament)|supermajor]], [[enneadecal]], [[neptune]], [[mitonic]], and [[mutt]]. It notably provides the [[optimal patent val]] for the rank-3 [[horwell]] temperament, and is also an excellent tuning for the 5-limit [[Helmholtz (temperament)|helmholtz]] temperament, tempering out 32805/32768, and the no-fives temperament tempering out {{monzo| -59 39 0 -1 }}.
Remarkable 5-limit commas 171et [[tempering out|tempers out]] are 32805/32768 ([[schisma]]), {{monzo| 1 -27 18 }} ([[ennealimma]]), {{monzo| -14 -19 19 }} ([[enneadeca]]), and {{monzo| -29 -11 20 }} ([[gammic comma]]), and remarkable 7-limit commas 171et tempers out are 2401/2400 ([[breedsma]]), 4375/4374 ([[ragisma]]), 65625/65536 ([[horwell comma]]), 250047/250000 ([[landscape comma]]), 420175/419904 ([[wizma]]), and 703125/702464 ([[meter]]). Therefore, 171et [[support]]s a number of notable 7-limit rank-2 temperaments: [[pontiac]], [[sesquiquartififths]], [[term]], [[ennealimmal]], [[tertiaseptal]], [[supermajor (temperament)|supermajor]], [[enneadecal]], [[neptune]], [[mitonic]], and [[mutt]]. It notably provides the [[optimal patent val]] for the rank-3 [[horwell]] temperament, and is also an excellent tuning for the 5-limit [[Helmholtz (temperament)|helmholtz]] temperament, tempering out 32805/32768, and the no-fives temperament tempering out {{monzo| -59 39 0 -1 }}.


All intervals with an odd limit below 10,000,000 in the 7-limit are mapped consistently by 171edo. Because of its accuracy in the 7-limit, the 171et mapping is an excellent and relatively simple way to classify commas by size. For example, one step represents [[225/224]], two steps [[126/125]], three steps [[81/80]], and four steps [[64/63]].
171edo is notably [[Consistency#Consistency to distance d|consistent to distance ''6'']] in the [[7-limit|7-prime]] [[15-odd-limit]], and to distance ''8'' in the [[9-odd-limit]]. No other edo is so consistent until [[3125edo]]. Because of its accuracy in the 7-limit, the 171et mapping is an excellent and relatively simple way to classify 7-limit commas by size. For example, one step represents [[225/224]], two steps [[126/125]], three steps [[81/80]], and four steps [[64/63]].


171edo is much less accurate in the 11-limit, but still quite useful as it is a good tuning (emphasizing accuracy in the 7-limit) for the important rank-3 temperament [[jove]], which tempers out [[243/242]] (rastma) and [[441/440]], not to mention [[540/539]] and 2401/2400. Jove can be extended by adding [[364/363]] for the 13-limit and [[595/594]] for the 17-limit, which 171edo also supports. Alternatively, the 171e val can be used, which tempers out [[385/384]]. In the 2.3.13 subgroup, it provides the optimal patent val for [[Glacier comma|glacier]], and is generally a great [[2.3.5.7.13 subgroup|2.3.5.7.13]] and 2.3.5.7.13.17 subgroup temperament.  
171edo is much less accurate in the 11-limit, but still quite useful as it is a good tuning (emphasizing accuracy in the 7-limit) for the important rank-3 temperament [[jove]], which tempers out [[243/242]] (rastma) and [[441/440]], not to mention [[540/539]] and 2401/2400. Jove can be extended by adding [[364/363]] for the 13-limit and [[595/594]] for the 17-limit, which 171edo also supports. Alternatively, the 171e val can be used, which tempers out [[385/384]]. In the 2.3.13 subgroup, it provides the optimal patent val for [[Glacier comma|glacier]], and is generally a good [[2.3.5.7.13 subgroup|2.3.5.7.13]] and better 2.3.5.7.13.17 subgroup temperament.  


171edo is an excellent tuning for the [[Carlos Gamma]] scale, since the difference between 5 steps of 171edo and 1 step of Carlos Gamma is only -0.010823 cents.  
171edo is an excellent tuning for the [[Carlos Gamma]] scale, since the difference between 5 steps of 171edo and 1 step of Carlos Gamma is only -0.010823 cents.  
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=== Subsets and supersets ===
=== Subsets and supersets ===
171 factors into primes as {{nowrap| 3<sup>2</sup> × 19 }}, and 171edo shares the nearly pure [[7/6]] of [[9edo]] and the nearly pure [[6/5]] of [[19edo]], with every 7-limit interval expressible in terms of 2, 6/5, 7/6, and any one of primes 3, 5, or 7. [[342edo]], which doubles 171, provides an excellent correction for the 11th harmonic.
171 factors into primes as {{nowrap| 3<sup>2</sup> × 19 }}, and 171edo shares the nearly pure [[7/6]] of [[9edo]] and the nearly pure [[6/5]] of [[19edo]], with every 7-limit interval expressible in terms of 2, 6/5, 7/6, and any one of primes 3, 5, or 7.  
 
[[342edo]], which doubles 171, provides an excellent correction for the 11th harmonic and is one of the most accurate [[11-limit]] temperaments, with unmatched relative error up until [[1848edo]].
 
[[684edo]], which quadruples it, achieves [[17-odd-limit]] consistency.


== Intervals ==
== Intervals ==
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| 62\171
| 62\171
|}
|}
=== 7-prime-limited odd-limit analysis ===
171edo is ''distinctly'' [[consistent]] and monotone up to the 7-prime-limited 45-odd-limit:
{{Databox
|collapse=true
|title=The 7-prime-limited 45-odd-limit, by 171edo mapping (SW3 format)
|text=
<pre>
(*
7-PL 45-OL odds:
1 3 5 7 9 15 21 25 27 35 45
  Mapping  Ratio    Error
*)
(*  7\171*) 36/35 (* +.352c *)
(*  9\171*) 28/27 (* +.197c *)
(* 10\171*) 25/24 (* -.497c *)
(* 12\171*) 21/20 (* -.257c *)
(* 16\171*) 16/15 (* +.549c *)
(* 17\171*) 15/14 (* -.145c *)
(* 19\171*) 27/25 (* +.096c *)
(* 22\171*) 35/32 (* -.754c *)
(* 26\171*) 10/9  (* +.052c *)
(* 28\171*) 28/25 (* +.293c *)
(* 29\171*) 9/8  (* -.401c *)
(* 33\171*) 8/7  (* -.405c *)
(* 38\171*) 7/6  (* -.204c *)
(* 42\171*) 32/27 (* +.602c *)
(* 43\171*) 25/21 (* -.092c *)
(* 45\171*) 6/5  (* +.148c *)
(* 54\171*) 56/45 (* +.345c *)
(* 55\171*) 5/4  (* -.349c *)
(* 61\171*) 32/25 (* +.698c *)
(* 62\171*) 9/7  (* +.004c *)
(* 64\171*) 35/27 (* -.152c *)
(* 67\171*) 21/16 (* -.605c *)
(* 71\171*) 4/3  (* +.201c *)
(* 74\171*) 27/20 (* -.253c *)
(* 78\171*) 48/35 (* +.553c *)
(* 81\171*) 25/18 (* -.296c *)
(* 83\171*) 7/5  (* -.056c *)
(* 84\171*) 45/32 (* -.750c *)
(* 87\171*) 64/45
(* 88\171*) 10/7
(* 90\171*) 36/25
(* 93\171*) 35/24
(* 97\171*) 40/27
(*100\171*) 3/2
(*104\171*) 32/21
(*107\171*) 54/35
(*109\171*) 14/9
(*110\171*) 25/16
(*116\171*) 8/5
(*117\171*) 45/28
(*126\171*) 5/3
(*128\171*) 42/25
(*129\171*) 27/16
(*133\171*) 12/7
(*138\171*) 7/4
(*142\171*) 16/9
(*143\171*) 25/14
(*145\171*) 9/5
(*149\171*) 64/35
(*152\171*) 50/27
(*154\171*) 28/15
(*155\171*) 15/8
(*159\171*) 40/21
(*161\171*) 48/25
(*162\171*) 27/14
(*164\171*) 35/18
(*171\171*) 2/1
</pre>
}}
The 7-prime-limited 49-odd-limit is where non-distinctness first shows up: namely, ~49/48 = ~50/49 (this is characteristic of all ennealimmal tunings). However, 171edo remains consistent up to much higher 7-prime-limited odd-limits (much higher than even [[99edo]]).


== Regular temperament properties ==
== Regular temperament properties ==
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| 2.88
| 2.88
|}
|}
* 171et is lower in relative error than any previous equal temperaments in the 7-limit and in the [[9-odd-limit]]. Not until [[441edo|441]] do we find a better equal temperaments in terms of absolute error, and not until [[3125edo|3125]] do we find one in terms of relative error.
* 171et is lower in relative error than any previous equal temperaments in the 7-limit. Not until [[441edo|441]] do we find a better equal temperaments in terms of absolute error, and not until [[3125edo|3125]] do we find one in terms of relative error.


=== Rank-2 temperaments ===
=== Rank-2 temperaments ===
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| 182.46
| 182.46
| 10/9
| 10/9
| [[Minortone]] / [[mitonic]] / mineral (171) / ore (171e) / goldmine (171ef)
| [[Mitonic]] / mineral (171) / ore (171e) / goldmine (171ef)
|-
|-
| 1
| 1
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| 498.25
| 498.25
| 4/3
| 4/3
| [[Helmholtz (temperament)|Helmholtz]] / [[pontiac]]
| [[Pontiac]]
|-
|-
| 1
| 1
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| 182.46
| 182.46
| 10/9
| 10/9
| [[Terrain]] / [[domain]]
| [[Domain (temperament)|Domain]]
|-
|-
| 3
| 3
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| 315.79<br>(49.12)
| 315.79<br>(49.12)
| 6/5<br>(36/35)
| 6/5<br>(36/35)
| [[Ennealimmal]] (171e) / ennealimmia (171) / ennealimnic (171) / ennealiminal (171ef)
| [[Ennealimmal]] / enneabiotic (171ef) / ennealympic (171) / ennealimnic (171) / ennealiminal (171ef)
|-
|-
| 9
| 9