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<span style="display: block; text-align: right;">[[de:Porcupine]]</span>
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'''Porcupine''' is a [[linear temperament]] in the [[porcupine family]] that tempers out [[250/243]], the porcupine [[comma]], and whose generator is somewhere around 160-165 cents. It can be thought of as a 5-[[Harmonic Limit|limit]], 7-limit, or 11-limit temperament, or a 2.3.5.11 [[subgroup temperament]]. It is one of the best temperaments in the 2.3.5.11 subgroup, with a unique combination of efficiency and accuracy.


'''Porcupine''' is a [[Regular_Temperaments|linear temperament]] in the [[Porcupine_family|porcupine family]] that tempers out 250/243, the porcupine [[Comma|comma]], and whose generator is somewhere around 160-165 cents. It can be thought of as a 5-[[Harmonic_Limit|limit]], 7-limit, or 11-limit temperament, or a 2.3.5.11 [[Subgroup_temperaments|subgroup temperament]]. It is one of the best temperaments in the 2.3.5.11 subgroup, with a unique combination of efficiency and accuracy.
The basic 5-limit harmonic structure of porcupine can be understood simply by noting that tempering out 250/243 makes (4/3)^2 equivalent to (6/5)^3. In perhaps more familiar musical terms, this means two "perfect fourths" equals three "minor thirds". As a consequence of this, 4/3 is divided into 3 equal parts, and 6/5 is divided into 2 of those same equal parts. This is obviously in stark contrast to [[12edo]], and to meantone, in which neither 4/3 nor 6/5 can be divided into any number of equal parts. The "equal tetrachord" formed by dividing 4/3 into 3 equal parts is a characteristic feature of many porcupine scales.


The basic 5-limit harmonic structure of porcupine can be understood simply by noting that tempering out 250/243 makes (4/3)^2 equivalent to (6/5)^3. In perhaps more familiar musical terms, this means two "perfect fourths" equals three "minor thirds". As a consequence of this, 4/3 is divided into 3 equal parts, and 6/5 is divided into 2 of those same equal parts. This is obviously in stark contrast to [[12edo|12edo]], and to meantone, in which neither 4/3 nor 6/5 can be divided into any number of equal parts. The "equal tetrachord" formed by dividing 4/3 into 3 equal parts is a characteristic feature of many porcupine scales.
[[File:porcupinesymmetricminor22edo.mp3]]


[[File:porcupinesymmetricminor22edo.mp3]]
Porcupine symmetric minor scale, containing two equal tetrachords with a major wholetone between them. (Tuning in [[22edo]])


Porcupine symmetric minor scale, containing two equal tetrachords with a major wholetone between them. (Tuning in [[22edo|22edo]])
[[File:porcupine.png]]


[[File:porcupine.png|alt=porcupine.png|porcupine.png]]
== Interval chain ==


==Interval chain==
{{Main|Porcupine intervals}}
Main article: [[Porcupine_intervals|Porcupine intervals]]


{| class="wikitable" style="text-align:center"  
{| class="wikitable center-all right-2 right-6"
! Generators
! Generators
! Cents
! Cents
Line 25: Line 30:
|-
|-
| 0
| 0
| style="text-align:right;" | 0.00
| 0.00
| 1/1
| 1/1
| P1
| P1
| 0
| 0
| style="text-align:right;" | 1200.00
| 1200.00
| 2/1
| 2/1
| P8
| P8
|-
|-
| 1
| 1
| style="text-align:right;" | 162.75
| 162.75
| 12/11~11/10~10/9
| 12/11~11/10~10/9
| vM2 = ^^m2
| vM2 = ^^m2
| -1
| -1
| style="text-align:right;" | 1037.25
| 1037.25
| 9/5~20/11~11/6
| 9/5~20/11~11/6
| ^m7 = vvM7
| ^m7 = vvM7
|-
|-
| 2
| 2
| style="text-align:right;" | 325.50
| 325.50
| 6/5~11/9
| 6/5~11/9
| ^m3 = vvM3
| ^m3 = vvM3
| -2
| -2
| style="text-align:right;" | 874.50
| 874.50
| 18/11~5/3
| 18/11~5/3
| vM6 = ^^m6
| vM6 = ^^m6
|-
|-
| 3
| 3
| style="text-align:right;" | 488.25
| 488.25
| 4/3
| 4/3
| P4
| P4
| -3
| -3
| style="text-align:right;" | 711.75
| 711.75
| 3/2
| 3/2
| P5
| P5
|-
|-
| 4
| 4
| style="text-align:right;" | 651.00
| 651.00
| 16/11~22/15
| 16/11~22/15
| v5 = ^^d5
| v5 = ^^d5
| -4
| -4
| style="text-align:right;" | 549.00
| 549.00
| 15/11~11/8
| 15/11~11/8
| ^4 = vvA4
| ^4 = vvA4
|-
|-
| 5
| 5
| style="text-align:right;" | 813.75
| 813.75
| 8/5
| 8/5
| ^m6 = vvM6
| ^m6 = vvM6
| -5
| -5
| style="text-align:right;" | 386.25
| 386.25
| 5/4
| 5/4
| vM3 = ^^m3
| vM3 = ^^m3
|-
|-
| 6
| 6
| style="text-align:right;" | 976.50
| 976.50
| 7/4~16/9
| 7/4~16/9
| m7
| m7
| -6
| -6
| style="text-align:right;" | 223.50
| 223.50
| 9/8~8/7
| 9/8~8/7
| M2
| M2
|-
|-
| 7
| 7
| style="text-align:right;" | 1139.25
| 1139.25
| 48/25~160/81
| 48/25~160/81
| v8 = ^^d8
| v8 = ^^d8
| -7
| -7
| style="text-align:right;" | 60.75
| 60.75
| 81/80~25/24
| 81/80~25/24
| ^1 = vvA1
| ^1 = vvA1
|-
|-
| 8
| 8
| style="text-align:right;" | 102.00
| 102.00
| 16/15~21/20
| 16/15~21/20
| ^m2 = vvM2
| ^m2 = vvM2
| -8
| -8
| style="text-align:right;" | 1098.00
| 1098.00
| 40/21~15/8
| 40/21~15/8
| vM7 = ^^m7
| vM7 = ^^m7
|-
|-
| 9
| 9
| style="text-align:right;" | 264.75
| 264.75
| 7/6
| 7/6
| m3
| m3
| -9
| -9
| style="text-align:right;" | 935.25
| 935.25
| 12/7
| 12/7
| M6
| M6
|-
|-
| 10
| 10
| style="text-align:right;" | 427.50
| 427.50
| 14/11
| 14/11
| v4 = ^^d4
| v4 = ^^d4
| -10
| -10
| style="text-align:right;" | 772.50
| 772.50
| 11/7
| 11/7
| ^5 = vvA5
| ^5 = vvA5
|-
|-
| 11
| 11
| style="text-align:right;" | 590.25
| 590.25
| 7/5
| 7/5
| ^d5 = vv5
| ^d5 = vv5
| -11
| -11
| style="text-align:right;" | 609.75
| 609.75
| 10/7
| 10/7
| vA4 = ^^4
| vA4 = ^^4
|-
|-
| 12
| 12
| style="text-align:right;" | 753.00
| 753.00
| 14/9
| 14/9
| m6
| m6
| -12
| -12
| style="text-align:right;" | 447.00
| 447.00
| 9/7
| 9/7
| M3
| M3
|}
|}
The specific tuning shown is the full 11-limit [[POTE_tuning|POTE tuning]], but of course there is a range of acceptible porcupine tunings that includes generators as small as 160 cents ([[15edo|15edo]]) and as large as 165.5 cents ([[29edo|29edo]]). (However, the 29edo patent val does not support 11-limit porcupine proper, not annihilating 64/63.)
The specific tuning shown is the full 11-limit [[POTE tuning]], but of course there is a range of acceptible porcupine tunings that includes generators as small as 160 cents ([[15edo]]) and as large as 165.5 cents ([[29edo]]). (However, the 29edo patent val does not support 11-limit porcupine proper, not annihilating [[64/63]].)


12/11, 11/10, and 10/9 are all represented by the same interval, the generator. This makes chords such as 8:9:10:11:12 exceptionally common and easy to find.
[[12/11]], [[11/10]], and [[10/9]] are all represented by the same interval, the generator. This makes chords such as 8:9:10:11:12 exceptionally common and easy to find.


{| class="wikitable"
{| class="wikitable"
Line 151: Line 156:
|-
|-
| 8:9:10:11:12 chord, in just intonation. <br> All intervals are slightly different.
| 8:9:10:11:12 chord, in just intonation. <br> All intervals are slightly different.
| Porcupine-tempered 8:9:10:11:12 chord, in [[22edo|22edo]]. <br> Except the first, the intervals are the same.
| Porcupine-tempered 8:9:10:11:12 chord, in [[22edo]]. <br> Except the first, the intervals are the same.
| Porcupine-tempered 8:9:10:11:12 chord, in [[29edo|29edo]]. <br> Except the first, the intervals are the same.
| Porcupine-tempered 8:9:10:11:12 chord, in [[29edo]]. <br> Except the first, the intervals are the same.
|}
|}


The 11/9 interval, usually considered a "neutral third", is in porcupine identical to the 6/5 "minor third". This means that the 27/20 "acute fourth" of the JI diatonic scale is equivalent to 11/8 (rather than becoming 4/3 as in meantone).
The [[11/9]] interval, usually considered a "neutral third", is in porcupine identical to the [[6/5]] "minor third". This means that the [[27/20]] "acute fourth" of the JI diatonic scale is equivalent to [[11/8]] (rather than becoming 4/3 as in meantone).


The characteristic small interval of porcupine, which is 60.75 cents in this tuning but can range from &lt;50 to 80 cents in general, represents both 25/24 and 81/80.
The characteristic small interval of porcupine, which is 60.75 cents in this tuning but can range from &lt;50 to 80 cents in general, represents both [[25/24]] and [[81/80]].


==Spectrum of Porcupine Tunings by Eigenmonzos==
== Spectrum of Porcupine Tunings by Eigenmonzos ==


{| class="wikitable"
{| class="wikitable"
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[8/5 12/7] eigenmonzos: [[porcupinewoo15|porcupinewoo15]] [[porcupinewoo22|porcupinewoo22]]
[8/5 12/7] eigenmonzos: [[porcupinewoo15|porcupinewoo15]] [[porcupinewoo22|porcupinewoo22]]


===Spectrum of Porcupinefish Tunings===
=== Spectrum of Porcupinefish Tunings ===


{| class="wikitable"
{| class="wikitable"
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|}
|}


==History==
== History ==
Porcupine temperament/scales were discovered by [[Dave_Keenan|Dave Keenan]], but didn't have a name until [[Herman_Miller|Herman Miller]] mentioned that his Mizarian Porcupine Overture in 15-tET had a section that pumps the 250:243 comma. Although this music did not use a Porcupine MOS or MODMOS (which would have 7 or 8 notes), the name was adopted for such scales as well, once the essentially one-to-one relationship between vanishing commas and sequences of DE scales was fully evident. It was clear that even though Herman's piece was in 15, 22 was a porcupine tuning par excellence, and that was an interesting development in itself.


==See also==
Porcupine temperament/scales were discovered by [[Dave Keenan]], but didn't have a name until [[Herman Miller]] mentioned that his Mizarian Porcupine Overture in 15-tET had a section that pumps the [[250/243|250:243 comma]]. Although this music did not use a Porcupine MOS or MODMOS (which would have 7 or 8 notes), the name was adopted for such scales as well, once the essentially one-to-one relationship between vanishing commas and sequences of DE scales was fully evident. It was clear that even though Herman's piece was in 15, 22 was a porcupine tuning par excellence, and that was an interesting development in itself.


* [[Chords_of_porcupine|Chords of porcupine]]
== See also ==
* [[Porcupine_Notation|Porcupine Notation]]
* [[Porcupine_modes|Porcupine modes]]
* [[Porcupine_Album_Project|Porcupine Album Project]]


==Musical examples==
* [[Chords of porcupine]]
* [[Porcupine Notation]]
* [[Porcupine modes]]
* [[Porcupine Album Project]]
 
== Musical examples ==


* ''[http://sites.google.com/site/teamouse/home#TOC-Mizarian-music Mizarian Porcupine Overture]'', [[Herman Miller]], 1999. (15edo, namesake of the temperament)
* ''[http://sites.google.com/site/teamouse/home#TOC-Mizarian-music Mizarian Porcupine Overture]'', [[Herman Miller]], 1999. (15edo, namesake of the temperament)
* ''[http://www.myspace.com/paulerlich/music/songs/glassic-in-22-tone-equal-temperament-45202095 Glassic]'', [[Paul Erlich]], [[22edo]] (at least the beginning part is in porcupine).
* ''[http://www.myspace.com/paulerlich/music/songs/glassic-in-22-tone-equal-temperament-45202095 Glassic]'', [[Paul Erlich]], [[22edo]] (at least the beginning part is in porcupine).
* ''[http://www.archive.org/download/NightOnPorcupineMountain/Genewardsmithmussorgsky-NightOnPorcupineMountain.mp3 Night on Porcupine Mountain]'', Gene Ward Smith and Modest Mussorgsky, [[22edo]].
* ''[http://www.archive.org/download/NightOnPorcupineMountain/Genewardsmithmussorgsky-NightOnPorcupineMountain.mp3 Night on Porcupine Mountain]'', [[Gene Ward Smith]] and Modest Mussorgsky, [[22edo]].
* ''[http://soundclick.com/share.cfm?id=8839060 being a]'', Andrew Heathwaite, 2010, 22edo, mode 3 1 3 3 3 3 3 3 of Porcupine[8].
* ''[http://soundclick.com/share.cfm?id=8839060 being a]'', [[Andrew Heathwaite]], 2010, 22edo, mode 3 1 3 3 3 3 3 3 of Porcupine[8].
* ''[http://micro.soonlabel.com/15-ET/daily20110619_millers_porcupine_7a.mp3 Playing Gently with Miller's Porcupine]'' by [[Chris Vaisvil]]
* ''[http://micro.soonlabel.com/15-ET/daily20110619_millers_porcupine_7a.mp3 Playing Gently with Miller's Porcupine]'' by [[Chris Vaisvil]]
* ''[http://micro.soonlabel.com/15-ET/daily20111231-porcupine15-indian.mp3 15 Porcupines in India]'', Sarangi, Tambura and Sitar improvisation by [[Chris Vaisvil]]
* ''[http://micro.soonlabel.com/15-ET/daily20111231-porcupine15-indian.mp3 15 Porcupines in India]'', Sarangi, Tambura and Sitar improvisation by [[Chris Vaisvil]]
Line 372: Line 378:
* [https://www.youtube.com/watch?v=se79rdp705Y Flying Straight Down] by [[John Moriarty]]
* [https://www.youtube.com/watch?v=se79rdp705Y Flying Straight Down] by [[John Moriarty]]


==Images==
== Images ==
[[File:porcupine8.jpg|alt=porcupine8.jpg|porcupine8.jpg]]       
 
[[Category:soft_redirect]]
[[File:porcupine8.jpg]]       
 
[[Category:Porcupine]]
[[Category:Temperament]]

Revision as of 10:46, 25 October 2020

Porcupine is a linear temperament in the porcupine family that tempers out 250/243, the porcupine comma, and whose generator is somewhere around 160-165 cents. It can be thought of as a 5-limit, 7-limit, or 11-limit temperament, or a 2.3.5.11 subgroup temperament. It is one of the best temperaments in the 2.3.5.11 subgroup, with a unique combination of efficiency and accuracy.

The basic 5-limit harmonic structure of porcupine can be understood simply by noting that tempering out 250/243 makes (4/3)^2 equivalent to (6/5)^3. In perhaps more familiar musical terms, this means two "perfect fourths" equals three "minor thirds". As a consequence of this, 4/3 is divided into 3 equal parts, and 6/5 is divided into 2 of those same equal parts. This is obviously in stark contrast to 12edo, and to meantone, in which neither 4/3 nor 6/5 can be divided into any number of equal parts. The "equal tetrachord" formed by dividing 4/3 into 3 equal parts is a characteristic feature of many porcupine scales.

Porcupine symmetric minor scale, containing two equal tetrachords with a major wholetone between them. (Tuning in 22edo)

Interval chain

Generators Cents Ratios Ups and Downs
notation
Generators 2/1 inverse Ratios Ups and Downs
notation
0 0.00 1/1 P1 0 1200.00 2/1 P8
1 162.75 12/11~11/10~10/9 vM2 = ^^m2 -1 1037.25 9/5~20/11~11/6 ^m7 = vvM7
2 325.50 6/5~11/9 ^m3 = vvM3 -2 874.50 18/11~5/3 vM6 = ^^m6
3 488.25 4/3 P4 -3 711.75 3/2 P5
4 651.00 16/11~22/15 v5 = ^^d5 -4 549.00 15/11~11/8 ^4 = vvA4
5 813.75 8/5 ^m6 = vvM6 -5 386.25 5/4 vM3 = ^^m3
6 976.50 7/4~16/9 m7 -6 223.50 9/8~8/7 M2
7 1139.25 48/25~160/81 v8 = ^^d8 -7 60.75 81/80~25/24 ^1 = vvA1
8 102.00 16/15~21/20 ^m2 = vvM2 -8 1098.00 40/21~15/8 vM7 = ^^m7
9 264.75 7/6 m3 -9 935.25 12/7 M6
10 427.50 14/11 v4 = ^^d4 -10 772.50 11/7 ^5 = vvA5
11 590.25 7/5 ^d5 = vv5 -11 609.75 10/7 vA4 = ^^4
12 753.00 14/9 m6 -12 447.00 9/7 M3

The specific tuning shown is the full 11-limit POTE tuning, but of course there is a range of acceptible porcupine tunings that includes generators as small as 160 cents (15edo) and as large as 165.5 cents (29edo). (However, the 29edo patent val does not support 11-limit porcupine proper, not annihilating 64/63.)

12/11, 11/10, and 10/9 are all represented by the same interval, the generator. This makes chords such as 8:9:10:11:12 exceptionally common and easy to find.

8:9:10:11:12 chord, in just intonation.
All intervals are slightly different.
Porcupine-tempered 8:9:10:11:12 chord, in 22edo.
Except the first, the intervals are the same.
Porcupine-tempered 8:9:10:11:12 chord, in 29edo.
Except the first, the intervals are the same.

The 11/9 interval, usually considered a "neutral third", is in porcupine identical to the 6/5 "minor third". This means that the 27/20 "acute fourth" of the JI diatonic scale is equivalent to 11/8 (rather than becoming 4/3 as in meantone).

The characteristic small interval of porcupine, which is 60.75 cents in this tuning but can range from <50 to 80 cents in general, represents both 25/24 and 81/80.

Spectrum of Porcupine Tunings by Eigenmonzos

Eigenmonzo Neutral Second
13/12 138.573
13/11 144.605
12/11 150.637
13/10 151.405
6/5 157.821
15/13 158.710
18/13 159.154
2\15 160.000
8/7 161.471
14/11 161.751
7/5 162.047
5\37 162.162
11/8 162.171 13- and 15-limit minimax
8\59 162.712
5/4 162.737 5-limit minimax
15/14 162.897
7/6 162.986
3\22 163.636
9/7 163.743 7- 9- and 11-limit minimax
16/15 163.966
7\51 164.706
11/10 165.004
4\29 165.517
15/11 165.762
4/3 166.015
14/13 166.037
11/9 173.704
16/13 179.736
10/9 182.404

[8/5 12/7] eigenmonzos: porcupinewoo15 porcupinewoo22

Spectrum of Porcupinefish Tunings

12/11 150.637
6/5 157.821
2\15 160.000
18/13 160.307
15/13 160.860
8/7 161.471
13/12 161.531
14/11 161.751
7/5 162.047
14/13 162.100
13/10 162.149
5\37 162.162
11/8 162.171
16/13 162.322
13/11 162.368 13- and 15-limit minimax
8\59 162.712
5/4 162.737
15/14 162.897
7/6 162.986
3\22 163.636
9/7 163.743
16/15 163.966
7\51 164.706
11/10 165.004
4\29 165.517
15/11 165.762
4/3 166.015
11/9 173.704
10/9 182.404

History

Porcupine temperament/scales were discovered by Dave Keenan, but didn't have a name until Herman Miller mentioned that his Mizarian Porcupine Overture in 15-tET had a section that pumps the 250:243 comma. Although this music did not use a Porcupine MOS or MODMOS (which would have 7 or 8 notes), the name was adopted for such scales as well, once the essentially one-to-one relationship between vanishing commas and sequences of DE scales was fully evident. It was clear that even though Herman's piece was in 15, 22 was a porcupine tuning par excellence, and that was an interesting development in itself.

See also

Musical examples

Images