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{{MOS scale properties}}
{{MOS scale properties}}


==== Proposed names ====
=== Proposed names ===
Mode names are from [[Porcupine Temperament Modal Harmony|Porcupine temperament modal harmony]]. Descriptive mode names are based on using 1-4-7, i.e. 3+3 triads as a basis for harmony.
Mode names are from [[Porcupine Temperament Modal Harmony|Porcupine temperament modal harmony]]. Descriptive mode names are based on using {{dash|1, 4, 7}}, i.e. 3+3 triads as a basis for harmony.
{| class="wikitable"
{{MOS modes
!Mode
| Mode names =
!UDP
octopus $
!Mode name
mantis $
!Descriptive mode name
dolphin $
|-
crab $
|LLLLLLLs
tuna $
|<nowiki>7|0</nowiki>
salmon $
|octopus
starfish $
|Bright quartal
whale $
|-
| Table Headers=Name Origin
|LLLLLLsL
| Table Entries=
|<nowiki>6|1</nowiki>
Bright quartal $
|mantis
Dark quartal $
|Dark quartal
Bright major $
|-
Middle major $
|LLLLLsLL
Dark major $
|<nowiki>5|2</nowiki>
Bright minor $
|dolphin
Middle minor $
|Bright major
Dark minor $
|-
}}
|LLLLsLLL
|<nowiki>4|3</nowiki>
|crab
|Middle major
|-
|LLLsLLLL
|<nowiki>3|4</nowiki>
|tuna
|Dark major
|-
|LLsLLLLL
|<nowiki>2|5</nowiki>
|salmon
|Bright minor
|-
|LsLLLLLL
|<nowiki>1|6</nowiki>
|starfish
|Middle minor
|-
|sLLLLLLL
|<nowiki>0|7</nowiki>
|whale
|Dark minor
|}


== Theory ==
== Theory ==
=== Low harmonic entropy scales ===
=== Low harmonic entropy scales ===
There are three notable [[harmonic entropy]] minima with this [[mos]] pattern. The lowest accuracy one is [[porcupine]], in which two generators make a [[6/5]] and three make a [[4/3]]. The range of porcupine tunings is about 2\15 to 3\22. Less well-known and more accurate is [[greeley]], in which two generators are still 6/5 but three fall quite short of a 4/3, but the scale happens to closely approximate a lot of higher-complexity intervals like [[10/7]], [[11/7]], etc. Thirdly and finally, [[tempering out]] [[4000/3993|S10/S11]] so that ([[4/3]])/([[11/10]])<sup>3</sup> is tempered out results in an unusually high accuracy and efficient rank-2 temperament in the 2.3.11/5 subgroup for which interpretation as a rank-3 temperament in 2.3.5.11 (the no-7's [[11-limit]]) is natural, making [[10/9]] and [[12/11]] [[square superparticular|equidistant from 11/10]] and offering many fruitful tempering opportunities. Note therefore that [[porkypine]] can be seen as a trivial tuning of [[4000/3993|pine]] tempering out [[100/99]] = S10 and [[121/120]] = S11.
There are three notable [[harmonic entropy]] minima with this [[mos]] pattern.
 
* The lowest accuracy one is [[porcupine]], in which two generators make a [[6/5]] and three make a [[4/3]]. The range of porcupine tunings is about 2\15 to 3\22.
* Less well-known and more accurate is [[greeley]], in which two generators are still 6/5 but three fall quite short of a 4/3, but the scale happens to closely approximate a lot of higher-complexity intervals like [[10/7]], [[11/7]], etc.
* Thirdly and finally, [[tempering out]] [[4000/3993|S10/S11]] so that ([[4/3]])/([[11/10]])<sup>3</sup> is tempered out results in an unusually high accuracy and efficient rank-2 temperament in the 2.3.11/5 subgroup for which interpretation as a rank-3 temperament in 2.3.5.11 (the no-7's [[11-limit]]) is natural, making [[10/9]] and [[12/11]] [[square superparticular|equidistant from 11/10]] and offering many fruitful tempering opportunities. Note therefore that [[porkypine]] can be seen as a trivial tuning of [[4000/3993|pine]] tempering out {{nowrap|[[100/99]] {{=}} S10}} and {{nowrap|[[121/120]] {{=}} S11}}.
 
== Scale tree ==
{{MOS tuning spectrum
| 5/2 = General range of porcupine
| 2/1 = Optimum rank range for porcupine
| 13/8 = Golden porcupine/hemikleismic
| 10/7 = General range of greeley
}}


==Scale tree==
{{Scale tree|Comments=5/2: General range of porcupine;
2/1: Optimum rank range for porcupine;
13/8: Golden porcupine/hemikleismic
10/7: General range of greeley}}
[[Category:8-tone scales]]
[[Category:8-tone scales]]