# Porcupine family

(Redirected from Nautilus)

The porcupine family is the rank-2 family of temperaments whose 5-limit parent comma is 250/243, also called the maximal diesis or porcupine comma.

Its monzo is [1 -5 3, and flipping that yields ⟨⟨3 5 1]] for the wedgie. This tells us the generator is a minor whole tone, the 10/9 interval, and that three of these add up to a perfect fourth (4/3), with two more giving the minor sixth (8/5). In fact, (10/9)3 = 4/3 × 250/243, and (10/9)5 = 8/5 × (250/243)2. 3\22 is a very recommendable generator, and mos scales of 7, 8 and 15 notes make for some nice scale possibilities.

Notice 250/243 = (55/54)(100/99), the temperament thus extends naturally to the 2.3.5.11 subgroup, sometimes known as porkypine.

The second comma of the normal comma list defines which 7-limit family member we are looking at. That means

Temperaments discussed elsewhere include jamesbond.

## Porcupine

Subgroup: 2.3.5

Comma list: 250/243

Mapping[1 2 3], 0 -3 -5]]

mapping generators: ~2, ~10/9
• CTE: ~2 = 1\1, ~10/9 = 164.1659
• POTE: ~2 = 1\1, ~10/9 = 163.950

### 2.3.5.11 subgroup (porkypine)

Subgroup: 2.3.5.11

Comma list: 55/54, 100/99

Sval mapping: [1 2 3 4], 0 -3 -5 -4]]

Gencom mapping: [1 2 3 0 4], 0 -3 -5 0 -4]]

gencom: [2 10/9; 55/54, 100/99]

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 163.8867
• POTE: ~2 = 1\1, ~11/10 = 164.0777

Optimal ET sequence: 7, 15, 22, 73ce, 95ce

#### Undecimation

Subgroup: 2.3.5.11.13

Comma list: 55/54, 100/99, 512/507

Sval mapping: [1 5 8 8 2], 0 -6 -10 -8 3]]

sval mapping generators: ~2, ~65/44

Optimal tunings:

• CTE: ~2 = 1\1, ~88/65 = 518.0865
• POTE: ~2 = 1\1, ~88/65 = 518.2094

Optimal ET sequence: 7, 23bc, 30, 37, 44

## Septimal porcupine

Septimal porcupine uses six of its minor tone generator steps to get to 7/4. For this to work you need a small minor tone such as 22edo provides, and once again 3\22 is a good tuning choice, though we might pick in preference 8\59, 11\81, or 19\140 for our generator.

Subgroup: 2.3.5.7

Comma list: 64/63, 250/243

Mapping[1 2 3 2], 0 -3 -5 6]]

Wedgie⟨⟨3 5 -6 1 -18 -28]]

• CTE: ~2 = 1\1, ~10/9 = 163.2032
• POTE: ~2 = 1\1, ~10/9 = 162.880
eigenmonzo (unchanged-interval) basis: 2.5
eigenmonzo (unchanged-interval) basis: 2.9/7
• 7- and 9-odd-limit diamond monotone: ~10/9 = [160.000, 163.636] (2\15 to 3\22)
• 7-odd-limit diamond tradeoff: ~10/9 = [157.821, 166.015]
• 9-odd-limit diamond tradeoff: ~10/9 = [157.821, 182.404]

### 11-limit

Subgroup: 2.3.5.7.11

Comma list: 55/54, 64/63, 100/99

Mapping: [1 2 3 2 4], 0 -3 -5 6 -4]]

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 163.1055
• POTE: ~2 = 1\1, ~11/10 = 162.747

Minimax tuning:

• 11-odd-limit: ~11/10 = [1/6 -1/6 0 1/12
eigenmonzo (unchanged-interval) basis: 2.9/7

Tuning ranges:

• 11-odd-limit diamond monotone: ~11/10 = [160.000, 163.636] (2\15 to 3\22)
• 11-odd-limit diamond tradeoff: ~11/10 = [150.637, 182.404]

Optimal ET sequence: 7, 15, 22, 37, 59

#### 13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 40/39, 55/54, 64/63, 66/65

Mapping: [1 2 3 2 4 4], 0 -3 -5 6 -4 -2]]

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 163.4425
• POTE: ~2 = 1\1, ~11/10 = 162.708

Minimax tuning:

• 13- and 15-odd-limit: ~10/9 = [1 0 0 0 -1/4
eigenmonzo (unchanged-interval) basis: 2.11

Tuning ranges:

• 13-odd-limit diamond monotone: ~11/10 = [160.000, 163.636] (2\15 to 3\22)
• 15-odd-limit diamond monotone: ~11/10 = 163.636 (3\22)
• 13- and 15-odd-limit diamond tradeoff: ~11/10 = [138.573, 182.404]

Optimal ET sequence: 7, 15, 22f, 37f

#### Porcupinefish

Subgroup: 2.3.5.7.11.13

Comma list: 55/54, 64/63, 91/90, 100/99

Mapping: [1 2 3 2 4 6], 0 -3 -5 6 -4 -17]]

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 162.6361
• POTE: ~2 = 1\1, ~11/10 = 162.277

Minimax tuning:

• 13- and 15-odd-limit: ~10/9 = [2/13 0 0 0 1/13 -1/13
eigenmonzo (unchanged-interval) basis: 2.13/11

Tuning ranges:

• 13-odd-limit diamond monotone: ~10/9 = [160.000, 162.162] (2\15 to 5\37)
• 15-odd-limit diamond monotone: ~10/9 = 162.162 (5\37)
• 13- and 15-odd-limit diamond tradeoff: ~10/9 = [150.637, 182.404]

Optimal ET sequence: 15, 22, 37

#### Pourcup

Subgroup: 2.3.5.7.11.13

Comma list: 55/54, 64/63, 100/99, 196/195

Mapping: [1 2 3 2 4 1], 0 -3 -5 6 -4 20]]

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 163.3781
• POTE: ~2 = 1\1, ~11/10 = 162.482

Minimax tuning:

• 13- and 15-odd-limit: ~11/10 = [1/14 0 0 -1/14 0 1/14
eigenmonzo (unchanged-interval) basis: 2.13/7

Optimal ET sequence: 15f, 22f, 37, 59f

#### Porkpie

Subgroup: 2.3.5.7.11.13

Comma list: 55/54, 64/63, 65/63, 100/99

Mapping: [1 2 3 2 4 3], 0 -3 -5 6 -4 5]]

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 163.6778
• POTE: ~2 = 1\1, ~11/10 = 163.688

Minimax tuning:

• 13- and 15-odd-limit: ~11/10 = [1/6 -1/6 0 1/12
eigenmonzo (unchanged-interval) basis: 2.9/7

Optimal ET sequence: 7, 15f, 22

## Opossum

Opossum can be described as 7d & 8d. Tempering out 28/27, the perfect fifth of three generator steps is conflated with not 32/21 as in porcupine but 14/9. Three such fifths or nine generator steps octave reduced give a flat 7/4. 2\15 is a good generator.

Subgroup: 2.3.5.7

Comma list: 28/27, 126/125

Mapping[1 2 3 4], 0 -3 -5 -9]]

Wedgie⟨⟨3 5 9 1 6 7]]

Optimal tuning (CTE): ~2 = 1\1, ~10/9 = 161.3063

### 11-limit

Subgroup: 2.3.5.7.11

Comma list: 28/27, 55/54, 77/75

Mapping: [1 2 3 4 4], 0 -3 -5 -9 -4]]

Optimal tuning (CTE): ~2 = 1\1, ~11/10 = 161.3646

Minimax tuning:

• 11-odd-limit eigenmonzo (unchanged-interval) basis: 2.7

Optimal ET sequence: 7d, 8d, 15

### 13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 28/27, 40/39, 55/54, 66/65

Mapping: [1 2 3 4 4 4], 0 -3 -5 -9 -4 -2]]

Optimal tuning (CTE): ~2 = 1\1, ~11/10 = 161.6312

Minimax tuning:

• 13- and 15-odd-limit eigenmonzo (unchanged-interval) basis: 2.7

Optimal ET sequence: 7d, 8d, 15, 38bceff

## Porky

Porky can be described as 7d & 22, suggesting a less sharp perfect fifth. 7\51 is a good generator.

Subgroup: 2.3.5.7

Comma list: 225/224, 250/243

Mapping[1 2 3 5], 0 -3 -5 -16]]

Wedgie⟨⟨3 5 16 1 17 23]]

• CTE: ~2 = 1\1, ~10/9 = 164.3913
• POTE: ~2 = 1\1, ~10/9 = 164.412
eigenmonzo (unchanged-interval) basis: 2.7/5

### 11-limit

Subgroup: 2.3.5.7.11

Comma list: 55/54, 100/99, 225/224

Mapping: [1 2 3 5 4], 0 -3 -5 -16 -4]]

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 164.3207
• POTE: ~2 = 1\1, ~11/10 = 164.552

Minimax tuning:

• 11-odd-limit: ~11/10 = [2/11 0 1/11 -1/11
eigenmonzo (unchanged-interval) basis: 2.7/5

Optimal ET sequence: 7d, 15d, 22, 51

### 13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 55/54, 65/64, 91/90, 100/99

Mapping: [1 2 3 5 4 3], 0 -3 -5 -16 -4 5]]

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 164.4782
• POTE: ~2 = 1\1, ~11/10 = 164.953

Optimal ET sequence: 7d, 22, 29, 51f, 80cdeff

## Coendou

Coendou can be described as 7 & 29, suggesting an even less sharp or near-just perfect fifth. 9\65 is a good generator.

Subgroup: 2.3.5.7

Comma list: 250/243, 525/512

Mapping[1 2 3 1], 0 -3 -5 13]]

Wedgie⟨⟨3 5 -13 1 -29 -44]]

• CTE: ~2 = 1\1, ~10/9 = 166.0938
• POTE: ~2 = 1\1, ~10/9 = 166.041
eigenmonzo (unchanged-interval) basis: 2.3

### 11-limit

Subgroup: 2.3.5.7.11

Comma list: 55/54, 100/99, 525/512

Mapping: [1 2 3 1 4], 0 -3 -5 13 -4]]

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 165.9246
• POTE: ~2 = 1\1, ~11/10 = 165.981

Minimax tuning:

• 11-odd-limit: ~11/10 = [2/3 -1/3
eigenmonzo (unchanged-interval) basis: 2.3

Optimal ET sequence: 7, 22d, 29, 65ce

### 13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 55/54, 65/64, 100/99, 105/104

Mapping: [1 2 3 1 4 3], 0 -3 -5 13 -4 5]]

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 166.0459
• POTE: ~2 = 1\1, ~11/10 = 165.974

Minimax tuning:

• 13- and 15-odd-limit: ~11/10 = [2/3 -1/3
eigenmonzo (unchanged-interval) basis: 2.3

Optimal ET sequence: 7, 22d, 29, 65cef

## Hystrix

Hystrix provides a less complex avenue to the 7-limit, with the generator taking on the role of approximating 8/7. Unfortunately in temperaments as in life you get what you pay for, and hystrix, for which a generator of 2\15 or 9\68 can be used, is a temperament for the adventurous souls who have probably already tried 15edo. They can try the even sharper fifth of hystrix in 68edo and see how that suits.

Subgroup: 2.3.5.7

Comma list: 36/35, 160/147

Mapping[1 2 3 3], 0 -3 -5 -1]]

Wedgie⟨⟨3 5 1 1 -7 -12]]

• CTE: ~2 = 1\1, ~10/9 = 165.1845
• POTE: ~2 = 1\1, ~10/9 = 158.868
eigenmonzo (unchanged-interval) basis: 2.5

### 11-limit

Subgroup: 2.3.5.7.11

Comma list: 22/21, 36/35, 80/77

Mapping: [1 2 3 3 4], 0 -3 -5 -1 -4]]

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 164.7684
• POTE: ~2 = 1\1, ~11/10 = 158.750

Optimal ET sequence: 7, 8d, 15d

## Oxygen

Oxygen is perhaps not meant to be used as a serious temperament of harmony. Its comma basis suggests potential utility to construct Fokker blocks.

Subgroup: 2.3.5.7

Comma list: 21/20, 175/162

Mapping[1 2 3 3], 0 -3 -5 -2]]

Wedgie⟨⟨3 5 2 1 -5 -9]]

• CTE: ~2 = 1\1, ~10/9 = 161.3408
• POTE: ~2 = 1\1, ~10/9 = 169.112

## Hedgehog

Hedgehog has a period 1/2 octave and a generator which can be taken to be 9/7 instead of 10/9. It also tempers out 245/243, the sensamagic comma. It is a strong extension of BPS (as BPS has no 2 or sqrt(2)). 22edo provides the obvious (i.e the only patent val) tuning, but if you are looking for an alternative you could try the 146 232 338 411] (146bccdd) val with generator 10\73, or you could try 164 cents if you are fond of round numbers. The 14-note mos gives scope for harmony while stopping well short of 22. A related temperament is echidna, which offers much more accuracy. They merge on 22edo.

Subgroup: 2.3.5.7

Comma list: 50/49, 245/243

Mapping[2 1 1 2], 0 3 5 5]]

mapping generators: ~7/5, ~9/7

Wedgie⟨⟨6 10 10 2 -1 -5]]

• CTE: ~7/5 = 1\2, ~9/7 = 435.2580
• POTE: ~7/5 = 1\2, ~9/7 = 435.648

### 11-limit

Subgroup: 2.3.5.7.11

Comma list: 50/49, 55/54, 99/98

Mapping: [2 1 1 2 4], 0 3 5 5 4]]

Optimal tunings:

• CTE: ~7/5 = 1\2, ~9/7 = 435.5281
• POTE: ~7/5 = 1\2, ~9/7 = 435.386

Optimal ET sequence: 8d, 14c, 22, 58ce

#### 13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 50/49, 55/54, 65/63, 99/98

Mapping: [2 1 1 2 4 3], 0 3 5 5 4 6]]

Optimal tunings:

• CTE: ~7/5 = 1\2, ~9/7 = 436.3087
• POTE: ~7/5 = 1\2, ~9/7 = 435.861

Optimal ET sequence: 8d, 14cf, 22

#### Urchin

Subgroup: 2.3.5.7.11.13

Comma list: 40/39, 50/49, 55/54, 66/65

Mapping: [2 1 1 2 4 6], 0 3 5 5 4 2]]

Optimal tunings:

• CTE: ~7/5 = 1\2, ~9/7 = 435.1856
• POTE: ~7/5 = 1\2, ~9/7 = 437.078

Optimal ET sequence: 14c, 22f

### Hedgepig

Subgroup: 2.3.5.7.11

Comma list: 50/49, 245/243, 385/384

Mapping: [2 1 1 2 12], 0 3 5 5 -7]]

Optimal tunings:

• CTE: ~7/5 = 1\2, ~9/7 = 435.3289
• POTE: ~7/5 = 1\2, ~9/7 = 435.425

Optimal ET sequence: 22

Music

## Nautilus

Subgroup: 2.3.5.7

Comma list: 49/48, 250/243

Mapping[1 2 3 3], 0 -6 -10 -3]]

mapping generators: ~2, ~21/20

Wedgie⟨⟨6 10 3 2 -12 -21]]

• CTE: ~2 = 1\1, ~21/20 = 81.9143
• POTE: ~2 = 1\1, ~21/20 = 82.505

### 11-limit

Subgroup: 2.3.5.7.11

Comma list: 49/48, 55/54, 245/242

Mapping: [1 2 3 3 4], 0 -6 -10 -3 -8]]

Optimal tunings:

• CTE: ~2 = 1\1, ~21/20 = 81.8017
• POTE: ~2 = 1\1, ~21/20 = 82.504

Optimal ET sequence: 14c, 15, 29, 44d

#### 13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 49/48, 55/54, 91/90, 100/99

Mapping: [1 2 3 3 4 5], 0 -6 -10 -3 -8 -19]]

Optimal tunings:

• CTE: ~2 = 1\1, ~21/20 = 81.9123
• POTE: ~2 = 1\1, ~21/20 = 82.530

Optimal ET sequence: 14cf, 15, 29, 44d

#### Belauensis

Subgroup: 2.3.5.7.11.13

Comma list: 40/39, 49/48, 55/54, 66/65

Mapping: [1 2 3 3 4 4], 0 -6 -10 -3 -8 -4]]

Optimal tunings:

• CTE: ~2 = 1\1, ~21/20 = 82.0342
• POTE: ~2 = 1\1, ~21/20 = 81.759

Optimal ET sequence: 14c, 15, 29f, 44dff

Music

## Ammonite

Subgroup: 2.3.5.7

Comma list: 250/243, 686/675

Mapping[1 5 8 10], 0 -9 -15 -19]]

mapping generators: ~2, ~9/7

Wedgie⟨⟨9 15 19 3 5 2]]

• CTE: ~2 = 1\1, ~9/7 = 454.5500
• POTE: ~2 = 1\1, ~9/7 = 454.448

### 11-limit

Subgroup: 2.3.5.7.11

Comma list: 55/54, 100/99, 686/675

Mapping: [1 5 8 10 8], 0 -9 -15 -19 -12]]

Optimal tunings:

• CTE: ~2 = 1\1, ~9/7 = 454.5050
• POTE: ~2 = 1\1, ~9/7 = 454.512

Optimal ET sequence: 8d, 21cde, 29, 37, 66

### 13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 55/54, 91/90, 100/99, 169/168

Mapping: [1 5 8 10 8 9], 0 -9 -15 -19 -12 -14]]

Optimal tunings:

• CTE: ~2 = 1\1, ~13/10 = 454.4798
• POTE: ~2 = 1\1, ~13/10 = 454.529

Optimal ET sequence: 8d, 21cdef, 29, 37, 66

## Ceratitid

Subgroup: 2.3.5.7

Comma list: 250/243, 1728/1715

Mapping[1 2 3 3], 0 -9 -15 -4]]

mapping generators: ~2, ~36/35

Wedgie⟨⟨9 15 4 3 -19 -33]]

• CTE: ~2 = 1\1, ~36/35 = 54.8040
• POTE: ~2 = 1\1, ~36/35 = 54.384

### 11-limit

Subgroup: 2.3.5.7.11

Comma list: 55/54, 100/99, 352/343

Mapping: [1 2 3 3 4], 0 -9 -15 -4 -12]]

Optimal tunings:

• CTE: ~2 = 1\1, ~36/35 = 54.7019
• POTE: ~2 = 1\1, ~36/35 = 54.376

Optimal ET sequence: 1ce, 21ce, 22

### 13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 55/54, 65/63, 100/99, 352/343

Mapping: [1 2 3 3 4 4], 0 -9 -15 -4 -12 -7]]

Optimal tunings:

• CTE: ~2 = 1\1, ~36/35 = 54.5751
• POTE: ~2 = 1\1, ~36/35 = 54.665

Optimal ET sequence: 1ce, 21cef, 22