26edo: Difference between revisions

m Style and formatting (1/2)
m Style and formatting (2/2)
Line 6: Line 6:
}}
}}
{{Infobox ET}}
{{Infobox ET}}
{{EDO intro|26}}


{{EDO intro|26}}
== Theory ==
== Theory ==
26edo tempers out [[81/80]] in the [[5-limit]], making it a [[meantone]] tuning with a very flat fifth.  
26edo tempers out [[81/80]] in the [[5-limit]], making it a [[meantone]] tuning with a very flat fifth.  
Line 34: Line 34:
|-
|-
! Degrees
! Degrees
! [[Cents|cents]]
! [[Cent]]s
! Approximate Ratios*
! Approximate Ratios*
! Interval<br>Name
! Interval<br>Name
Line 341: Line 341:
For a more complete list, see [[Ups and downs notation #Chord names in other EDOs]].
For a more complete list, see [[Ups and downs notation #Chord names in other EDOs]].


== Selected just intervals approximated ==
== Approximation to JI ==
=== 15-odd-limit interval mappings ===
=== 15-odd-limit interval mappings ===
The following table shows how [[15-odd-limit intervals]] are represented in 26edo. Prime harmonics are in '''bold'''; intervals with a non-[[consistent]] mapping are in ''italic''.  
The following table shows how [[15-odd-limit intervals]] are represented in 26edo. Prime harmonics are in '''bold'''; intervals with a non-[[consistent]] mapping are in ''italic''.  


{| class="wikitable center-all"
{| class="wikitable mw-collapsible mw-collapsed center-all"
|+Direct mapping (even if inconsistent)
|+style=white-space:nowrap| 15-odd-limit intervals by direct approximation (even if inconsistent)  
|-
|-
! Interval, complement
! Interval, complement
Line 423: Line 423:
| 21.823
| 21.823
|}
|}
{{15-odd-limit|26}}


{| class="wikitable" style="text-align:center;"
== Approximation to irrational intervals ==
|+Patent val mapping
|-
! Interval, complement
! Error (abs, [[Cent|¢]])
|-
| [[13/12]], [[24/13]]
| 0.111
|-
| '''[[8/7]], [[7/4]]'''
| '''0.405'''
|-
| [[14/11]], [[11/7]]
| 2.123
|-
| [[10/9]], [[9/5]]
| 2.212
|-
| '''[[11/8]], [[16/11]]'''
| '''2.528'''
|-
| [[13/10]], [[20/13]]
| 7.325
|-
| [[6/5]], [[5/3]]
| 7.436
|-
| [[18/13]], [[13/9]]
| 9.536
|-
| '''[[4/3]], [[3/2]]'''
| '''9.647'''
|-
| '''[[16/13]], [[13/8]]'''
| '''9.758'''
|-
| [[7/6]], [[12/7]]
| 10.052
|-
| [[14/13]], [[13/7]]
| 10.163
|-
| [[12/11]], [[11/6]]
| 12.176
|-
| [[13/11]], [[22/13]]
| 12.287
|-
| [[15/13]], [[26/15]]
| 16.972
|-
| '''[[5/4]], [[8/5]]'''
| '''17.083'''
|-
| [[7/5]], [[10/7]]
| 17.488
|-
| [[9/8]], [[16/9]]
| 19.295
|-
| [[11/10]], [[20/11]]
| 19.611
|-
| [[9/7]], [[14/9]]
| 19.699
|-
| [[11/9]], [[18/11]]
| 21.823
|-
| ''[[16/15]], [[15/8]]''
| ''26.730''
|-
| ''[[15/14]], [[28/15]]''
| ''27.135''
|-
| ''[[15/11]], [[22/15]]''
| ''29.258''
|}
 
== Acoustic π just in between the ϕ intervals ==
After [[13edo#Phi vibes|13edo]], the weird coïncidences continue: [[11/7#Proximity with π/2|acoustic π/2]] (17\26) is just in between [[13edo#Phi vibes|the ϕ intervals provided by 13edo]] (16\26 for [[Logarithmic phi|logarithmic ϕ]]/2, and 18\26 for [[Acoustic phi|acoustic ϕ]]).
After [[13edo#Phi vibes|13edo]], the weird coïncidences continue: [[11/7#Proximity with π/2|acoustic π/2]] (17\26) is just in between [[13edo#Phi vibes|the ϕ intervals provided by 13edo]] (16\26 for [[Logarithmic phi|logarithmic ϕ]]/2, and 18\26 for [[Acoustic phi|acoustic ϕ]]).


Not until 1076edo do we find a better EDO in terms of relative error on these intervals (which is not a very relevant EDO for logarithmic ϕ, since 1076 does not belong to the Fibonacci sequence).
Not until 1076edo do we find a better edo in terms of relative error on these intervals (which is not a very relevant edo for logarithmic ϕ, since 1076 does not belong to the Fibonacci sequence).


However, it should be noted that [[Logarithmic constants VS acoustic constants|from an acoustic perspective]], acoustic π and acoustic ϕ are both better represented on [[23edo]].
However, it should be noted that [[Logarithmic constants VS acoustic constants|from an acoustic perspective]], acoustic π and acoustic ϕ are both better represented on [[23edo]].
Line 537: Line 459:
== Regular temperament properties ==
== Regular temperament properties ==
{| class="wikitable"
{| class="wikitable"
! rowspan="2" |[[Just intonation subgroup|Subgroup]]
! rowspan="2" | [[Just intonation subgroup|Subgroup]]
! rowspan="2" |[[Comma basis|Comma List]]
! rowspan="2" | [[Comma basis|Comma List]]
! rowspan="2" |[[Mapping]]
! rowspan="2" | [[Mapping]]
! rowspan="2" |Optimal
! rowspan="2" | Optimal<br>8ve Stretch (¢)
8ve Stretch (¢)
! colspan="2" | Tuning Error
! colspan="2" |Tuning Error
|-
|-
![[TE error|Absolute]] (¢)
! [[TE error|Absolute]] (¢)
![[TE simple badness|Relative]] (%)
! [[TE simple badness|Relative]] (%)
|-
|-
|2.3
| 2.3
|[-41 26⟩
| [-41 26⟩
|[⟨26 41]]
| [⟨26 41]]
| +3.043
| +3.043
|3.05
| 3.05
|6.61
| 6.61
|-
|-
|2.3.5
| 2.3.5
|81/80, 78125/73728
| 81/80, 78125/73728
|[⟨26 41 60]]
| [⟨26 41 60]]
| +4.489
| +4.489
|3.22
| 3.22
|6.98
| 6.98
|-
|-
|2.3.5.7
| 2.3.5.7
|50/49, 81/80, 405/392
| 50/49, 81/80, 405/392
|[⟨26 41 60 73]]
| [⟨26 41 60 73]]
| +3.324
| +3.324
|3.44
| 3.44
|7.45
| 7.45
|-
|-
|2.3.5.7.11
| 2.3.5.7.11
|45/44, 50/49, 81/80, 99/98
| 45/44, 50/49, 81/80, 99/98
|[⟨26 41 60 73 90]]
| [⟨26 41 60 73 90]]
| +2.509
| +2.509
|3.48
| 3.48
|7.53
| 7.53
|-
|-
|2.3.5.7.11.13
| 2.3.5.7.11.13
|45/44, 50/49, 65/64, 78/77, 81/80
| 45/44, 50/49, 65/64, 78/77, 81/80
|[⟨26 41 60 73 90 96]]
| [⟨26 41 60 73 90 96]]
| +2.531
| +2.531
|3.17
| 3.17
|6.87
| 6.87
|-
|-
|2.3.5.7.11.13.17
| 2.3.5.7.11.13.17
|45/44, 50/49, 65/64 78/77, 81/80, 85/84
| 45/44, 50/49, 65/64 78/77, 81/80, 85/84
|[⟨26 41 60 73 90 96 106]]
| [⟨26 41 60 73 90 96 106]]
| +2.613
| +2.613
|2.94
| 2.94
|6.38
| 6.38
|-
|-
|2.3.5.7.11.13.17.19
| 2.3.5.7.11.13.17.19
|45/44, 50/49, 57/56, 65/64, 78/77, 81/80, 85/84
| 45/44, 50/49, 57/56, 65/64, 78/77, 81/80, 85/84
|[⟨26 41 60 73 90 96 106 110]]
| [⟨26 41 60 73 90 96 106 110]]
| +2.894
| +2.894
|2.85
| 2.85
|6.18
| 6.18
|}
|}
26et is lower in relative error than any previous equal temperaments in the [[17-limit|17-]], [[19-limit|19-]], [[23-limit|23-]], and [[29-limit]] (using the 26i val for the 23- and 29-limit). The next equal temperaments performing better in those subgroups are [[27edo|27eg]], 27eg, [[29edo|29g]], and [[46edo|46]], respectively.  
26et is lower in relative error than any previous equal temperaments in the [[17-limit|17-]], [[19-limit|19-]], [[23-limit|23-]], and [[29-limit]] (using the 26i val for the 23- and 29-limit). The next equal temperaments performing better in those subgroups are [[27edo|27eg]], 27eg, [[29edo|29g]], and [[46edo|46]], respectively.  
Line 675: Line 596:
[[Gamelismic_clan#Unidec-Hendec|Hendec]], the 13-limit 26&amp;46 temperament with generator ~10/9, concentrates the intervals of greatest accuracy in 26et into the lower ranges of complexity. It has a period of half an octave, with 13/12 reachable by four generators, 8/7 by two, 14/11 by one, 10/9 by one, and 11/8 by three. All of these are tuned to within 2.5 cents of accuracy.
[[Gamelismic_clan#Unidec-Hendec|Hendec]], the 13-limit 26&amp;46 temperament with generator ~10/9, concentrates the intervals of greatest accuracy in 26et into the lower ranges of complexity. It has a period of half an octave, with 13/12 reachable by four generators, 8/7 by two, 14/11 by one, 10/9 by one, and 11/8 by three. All of these are tuned to within 2.5 cents of accuracy.


== Commas ==
=== Commas ===
26et [[tempers out]] the following [[commas]]. (Note: This assumes the [[val]] {{val| 26 41 60 73 90 96 }}.)
26et [[tempers out]] the following [[commas]]. (Note: This assumes the [[val]] {{val| 26 41 60 73 90 96 }}.)


Line 822: Line 743:
<references/>
<references/>


== Orgone Temperament ==
== Scales ==
[[Andrew_Heathwaite|Andrew Heathwaite]] first proposed [[Orgonia|orgone]] temperament to take advantage of 26edo's excellent 11 and 7 approximations. 7 degrees of 26edo is a wide minor third of approximately 323.077 cents, and that interval taken as a generator produces 7-tone and 11-tone MOS scales:
=== Orgone temperament ===
[[Andrew Heathwaite]] first proposed [[Orgonia|orgone]] temperament to take advantage of 26edo's excellent 11 and 7 approximations. 7 degrees of 26edo is a wide minor third of approximately 323.077 cents, and that interval taken as a generator produces 7-tone and 11-tone MOS scales:


The 7-tone scale in degrees-in-between: 5 2 5 2 5 2 5. [[MOSScales|MOS]] of type [[4L_3s|4L 3s (mish)]].
The 7-tone scale in degrees-in-between: 5 2 5 2 5 2 5. [[MOSScales|MOS]] of type [[4L_3s|4L 3s (mish)]].
Line 834: Line 756:


The primary triad for orgone temperament is 8:11:14 and its subharmonic inversion, which these scales have in abundance. 2g approximates [[16/11|16:11]] and 3g approximates [[7/4|7:4]] (and I would call that the definition of Orgone Temperament). That also implies that g approximates the difference between 7:4 and 16:11, which is 77:64, about 320.1 cents.
The primary triad for orgone temperament is 8:11:14 and its subharmonic inversion, which these scales have in abundance. 2g approximates [[16/11|16:11]] and 3g approximates [[7/4|7:4]] (and I would call that the definition of Orgone Temperament). That also implies that g approximates the difference between 7:4 and 16:11, which is 77:64, about 320.1 cents.


[[File:orgone_heptatonic.jpg|alt=orgone_heptatonic.jpg|orgone_heptatonic.jpg]]
[[File:orgone_heptatonic.jpg|alt=orgone_heptatonic.jpg|orgone_heptatonic.jpg]]


== Additional Scalar Bases Available in 26-EDO ==
=== Additional scalar bases available ===
Since the perfect 5th in 26-EDO spans 15 degrees, it can be divided into three equal parts (each approximately an 8/7) as well as five equal parts (each approximately a 13/12). The former approach produces MOS at 1L+4s, 5L+1s, and 5L+6s (5 5 5 5 6, 5 5 5 5 5 1, and 4 1 4 1 4 1 4 1 4 1 1 respectively), and is excellent for 4:6:7 triads. The latter produces MOS at 1L+7s and 8L+1s (3 3 3 3 3 3 3 5 and 3 3 3 3 3 3 3 3 2 respectively), and is fairly well-supplied with 4:6:7:11:13 pentads. It also works well for more conventional (though further from Just) 6:7:9 triads, as well as 4:5:6 triads that use the worse mapping for 5 (making 5/4 the 415.38-cent interval).
Since the perfect 5th in 26edo spans 15 degrees, it can be divided into three equal parts (each approximately an 8/7) as well as five equal parts (each approximately a 13/12). The former approach produces MOS at 1L+4s, 5L+1s, and 5L+6s (5 5 5 5 6, 5 5 5 5 5 1, and 4 1 4 1 4 1 4 1 4 1 1 respectively), and is excellent for 4:6:7 triads. The latter produces MOS at 1L+7s and 8L+1s (3 3 3 3 3 3 3 5 and 3 3 3 3 3 3 3 3 2 respectively), and is fairly well-supplied with 4:6:7:11:13 pentads. It also works well for more conventional (though further from Just) 6:7:9 triads, as well as 4:5:6 triads that use the worse mapping for 5 (making 5/4 the 415.38-cent interval).


-Igs
-Igs
Line 932: Line 852:
* [[Lumatone mapping for 26edo]]
* [[Lumatone mapping for 26edo]]


[[Category:26edo| ]] <!-- main article -->
[[Category:Equal divisions of the octave|##]] <!-- 2-digit number -->
[[Category:Listen]]
[[Category:Listen]]
[[Category:Twentuning]]
[[Category:Twentuning]]