Semaphore–chromatic equivalence continuum: Difference between revisions

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Created page. While dicot-semaphore-blackwood already exists, it is a user page and explicitly works with 10edo, while this works with decimal and is a mainspace page.
 
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The '''semaphore-chromatic equivalence continuum''' is a continuum of 7-limit rank-3 temperament families which equate a number of [[49/48|semaphore commas (49/48)]] with a [[25/24|classic chromatic semitone (25/24)]]. This continuum is theoretically interesting in that these are all 7-limit rank-3 temperament families supported by [[decimal]] temperament. 
{{Mathematical interest}}


All temperaments in the continuum satisfy (49/48)<sup>''n''</sup> ~ 25/24. Varying ''n'' results in different temperament families listed in the table below. It converges to [[semaphore]] as ''n'' approaches infinity. If we allow non-integer and infinite ''n'', the continuum describes the set of all [[7-limit]] temperament families supported by decimal (due to it being the unique rank-2 temperament that tempers both commas and thus tempers all combinations of them). The just value of ''n'' is approximately 1.9797965913603088..., and temperaments having ''n'' near this value will be more accurate. As this value is so close to 2, temperaments tempering out the [[2401/2400|breedsma (2401/2400)]] are unusually accurate.
The '''semaphore–chromatic equivalence continuum''' is a continuum of 7-limit rank-3 temperament families which equate a number of [[49/48|semaphore commas (49/48)]] with a [[25/24|classic chromatic semitone (25/24)]]. This continuum is theoretically interesting in that these are all 7-limit rank-3 temperament families supported by [[decimal]] temperament. 
{| class="wikitable center-1 center-2"
 
|+Temperaments in the continuum
All temperaments in the continuum satisfy {{nowrap|(49/48)<sup>''n''</sup> ~ 25/24}}. Varying ''n'' results in different temperament families listed in the table below. It converges to [[semaphore]] as ''n'' approaches infinity. If we allow non-integer and infinite ''n'', the continuum describes the set of all [[7-limit]] temperament families supported by decimal (due to it being the unique rank-2 temperament that tempers both commas and thus tempers all combinations of them). The just value of ''n'' is approximately 1.9797965913603088..., and temperaments having ''n'' near this value will be more accurate. As this value is so close to 2, temperaments tempering out the [[2401/2400|breedsma (2401/2400)]] are unusually accurate. It is even closer to 196/99, but the equivalent comma, while tiny even for an [[unnoticeable comma]] at 0.004907{{cent}}, is unreasonably complex, with a monzo of {{monzo|-487 -97 -198 392}}.
 
{| class="wikitable center-1"
|+ style="font-size: 105%;" | Temperaments in the continuum
|-
! rowspan="2" | ''n''
! rowspan="2" | Temperament
! colspan="2" | Comma
|-
! Ratio
! Monzo
|-
| −1
| 4 & 10 & 12d
| 1225/1152
| {{Monzo| -7 -2 2 2 }}
|-
|-
! rowspan="2" |''n''
| 0
! rowspan="2" |Temperament
| [[Dicot]] expansion
! colspan="2" |Comma
| [[25/24]]
| {{Monzo| -3 -1 2 0 }}
|-
|-
!Ratio
| 1
!Monzo
| [[Jubilismic]]
| [[50/49]]
| {{Monzo| 1 0 2 -2 }}
|-
|-
| -1
| 2
|10 & 4 & 12d
| [[Breed (temperament)|Breed]]
|1225/1152
| [[2401/2400]]
|{{monzo|-7 -2 2 2}}
| {{Monzo| -5 -1 -2 4 }}
|-
|-
|0
| 3
|[[Dicot]]
| 46 & 50 & 60
|[[25/24]]
| 117649/115200
|{{monzo|-3 -1 2 0}}
| {{monzo|-9 -2 -2 6}}
|-
|-
|1
|
|[[Jubilismic temperament|Jubilismic]]
|
|[[50/49]]
|
|{{monzo|1 0 2 -2}}
|
|-
|-
|2
|
|[[Breed (temperament)|Breed]]
| [[Semaphoresmic]]
|[[2401/2400]]
| [[49/48]]
|{{monzo|-5 -1 -2 4}}
| {{monzo| -4 -1 0 2 }}
|}
 
{| class="wikitable center-1"
|+ style="font-size: 105%;" | Temperaments with non-integer ''n''
|-
|-
|3
! rowspan="2" | ''n''
|46 & 60 & 50
! rowspan="2" | Temperament
|117649/115200
! colspan="2" | Comma
|{{monzo|-9 -2 -2 6}}
|-
|-
|…
! Ratio
|…
! Monzo
|…
|…
|-
|-
|
| 196/99
|[[Semaphore]]
| 4 & 10 & 3299cd
|[[49/48]]
| 664 digits
|{{monzo| -4 -1 0 2}}
| {{Monzo| -487 -97 -198 392 }}
|}
|}
[[Category:Equivalence continua]]
[[Category:Equivalence continua]]