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| Prime factorization = 17
| Prime factorization = 17
| Subgroup = 2.3.7.11.13
| Subgroup = 2.3.7.11.13
| Step size = 70.588
| Step size = 70.588¢
| Fifth type = [[leapfrog]]/[[archy]] 10\17 705.88¢ (+3.927¢)
| Fifth type = [[leapfrog]]/[[archy]] 10\17 = 705.88¢
| Major 2nd = 3\17 = 212¢
| Minor 2nd = 1\17 = 71¢
| Augmented 1sn = 2\17 = 141¢
| Common uses = diatonic (often neo-medieval), Westernized maqam
| Common uses = diatonic (often neo-medieval), Westernized maqam
| Important MOS = diatonic ([[leapfrog]]/[[archy]]) 5L2s 1221222 (10\17, 1\1)<br/>[[maqamic]] 3L4s 3232322 (5\17, 1\1)<br/>[[maqamic]] 7L3s 2221221221 (5\17, 1\1)<br/>[[lovecraft]] 4L5s 313131311 (4\17, 1\1)
| Important MOS = diatonic ([[leapfrog]]/[[archy]]) 5L2s 1221222 (10\17, 1\1)<br/>[[maqamic]] 3L4s 3232322 (5\17, 1\1)<br/>[[maqamic]] 7L3s 2221221221 (5\17, 1\1)<br/>[[lovecraft]] 4L5s 313131311 (4\17, 1\1)
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17 tone equal temperament, or 17-EDO, divides the octave in 17 equal steps, each 70.588 [[cent]]s in size. It is the seventh [[prime numbers|prime]] [[EDO]], following [[13edo]] and coming before [[19edo]].
17 tone equal temperament, or 17-EDO, divides the octave in 17 equal steps, each 70.588 [[cent]]s in size. It is the seventh [[prime numbers|prime]] [[EDO]], following [[13edo]] and coming before [[19edo]].
== Introductory materials ==
* [[SeventeenTheory]], an introduction to 17-EDO theory, through the eyes of the [[SeventeenTonePianoProject]].
* [http://anaphoria.com/Secor17puzzle.pdf The 17-tone Puzzle] by George Secor, another introduction into 17-EDO theory.
* [[17edo Solfege]]
* [[17edo tetrachords]]
* [http://microtonalismo.com/proyecto-xvii Proyect 17-Perú] {{forbidden}}


== Theory ==
== Theory ==
17-EDO can plausibly be treated as a 2.3.25.7.11.13.23 subgroup temperament, for which it is quite accurate (though the 7-limit ratios are generally not as well-represented as those of the other integers). Because the 3, 7, 11, and 13 are all sharp, it adapts well to octave shrinking; [[27edt]] (a variant of 17edo in which the octaves are flattened by ~2.5 cents) is a good alternative. Another one is [[44ed6]].
{| class="wikitable center-all"
! colspan="2" |
! prime 2
! prime 3
! prime 5
! prime 7
! prime 11
! prime 13
!prime 17
!prime 19
!prime 23
|-
! rowspan="2" | Error
! absolute ([[cent|¢]])
| 0
|  +3.93
|  -33.4
|  +19.4
|  +13.4
|  +6.5
|  -34.3
|  -15.2
|  +7.0
|-
![[Relative error|relative]] (%)
| 0
|  +6
|  -47
|  +27
|  +19
|  +9
|  -49
|  -21
|  +10
|-
! colspan="2" |[[nearest edomapping]]
|17
|10
|5
|14
|8
|12
|1
|4
|9
|-
! colspan="2" |[[fifthspan]]
| 0
|  +1
|  -8
|  -2
|  -6
|  +8
|  -5
|  -3
|  +6
|}17-EDO can plausibly be treated as a 2.3.25.7.11.13.23 subgroup temperament, for which it is quite accurate (though the 7-limit ratios are generally not as well-represented as those of the other integers). Because the 3, 7, 11, and 13 are all sharp, it adapts well to octave shrinking; [[27edt]] (a variant of 17edo in which the octaves are flattened by ~2.5 cents) is a good alternative. Another one is [[44ed6]].


As a no-fives system, it is best used with timbres in which harmonic multiples of 5 are attenuated or absent. Also, the standard major chord (4:5:6) cannot be used since it includes the fifth harmonic.
As a no-fives system, it is best used with timbres in which harmonic multiples of 5 are attenuated or absent. Also, the standard major chord (4:5:6) cannot be used since it includes the fifth harmonic.
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! Edo steps
! Edo steps
! Cents
! Cents
! colspan="2" | Names of Intervals
! colspan="2" | Names of Intervals, extended
! Note Name
pythagorean note names
! [[Ups and Downs Notation]]
! colspan="3" |[[Ups and Downs Notation]]
! Approximate Ratios*
! Approximate Ratios*
! Temperament(s) generated
! Temperament(s) generated
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| 0.00
| 0.00
| Unison
| Unison
| P1
| C
| C
|unison
|P1
| C
| C
| 1/1
| 1/1
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| 70.59
| 70.59
| Super Unison/Minor Second
| Super Unison/Minor Second
| m2
| Db <br> (B#)
| Db <br> (B#)
|minor 2nd
|m2
| ^C
| ^C
| [[25/24]], [[26/25]], [[33/32]], [[24/23]]
| [[25/24]], [[26/25]], [[33/32]], [[24/23]]
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| 141.18
| 141.18
| Augmented Unison/Neutral Second
| Augmented Unison/Neutral Second
| ~2
| C#
| C#
|mid 2nd
|~2
| vD
| vD
| [[13/12]], [[12/11]], [[14/13]], [[25/23]]
| [[13/12]], [[12/11]], [[14/13]], [[25/23]]
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| 211.76
| 211.76
| Major Second/Sub Third
| Major Second/Sub Third
| M2
| D
| D
|major 2nd
|M2
| D
| D
| [[9/8]], [[8/7]], [[28/25]], [[25/22]], [[26/23]]
| [[9/8]], [[8/7]], [[28/25]], [[25/22]], [[26/23]]
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| 282.35
| 282.35
| Minor Third/Super Second
| Minor Third/Super Second
| m3
| Eb
| Eb
|minor 3rd
|m3
| ^D
| ^D
| [[13/11]], [[7/6]]
| [[13/11]], [[7/6]]
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| 5
| 5
| 352.94
| 352.94
| Augmented Second/Neutral Third/ <br> Diminished Fourth
| Augmented Second/Neutral
| ~3
Third/Diminished Fourth
| D# <br> (Fb)
| D# <br> (Fb)
|mid 3rd
|~3
| vE
| vE
| [[11/9]], [[16/13]], [[28/23]]
| [[11/9]], [[16/13]], [[28/23]]
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| 423.53
| 423.53
| Major Third/Sub Fourth
| Major Third/Sub Fourth
| M3
| E
| E
|major 3rd
|M3
| E
| E
| [[32/25]], [[9/7]], [[14/11]], [[33/26]], [[23/18]]
| [[32/25]], [[9/7]], [[14/11]], [[33/26]], [[23/18]]
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| 494.12
| 494.12
| Perfect Fourth
| Perfect Fourth
| P4
| F
| F
|perfect 4th
|P4
| F
| F
| [[4/3]]
| [[4/3]]
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| 564.71
| 564.71
| Super Fourth/Diminshed Fifth
| Super Fourth/Diminshed Fifth
| ^4, ~4, <br> d5
| Gb <br> (E#)
| Gb <br> (E#)
|mid 4th,
diminished 5th
|~4,
d5
| ^F
| ^F
| [[11/8]], [[18/13]], [[32/23]]
| [[11/8]], [[18/13]], [[32/23]]
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| 635.29
| 635.29
| Augmented Fourth/Sub Fifth
| Augmented Fourth/Sub Fifth
| A4, <br> v5, ~5
| F#
| F#
|augmented 4th,
mid 5th
|A4, ~5
| vG
| vG
| [[16/11]], [[13/9]], [[23/16]]
| [[16/11]], [[13/9]], [[23/16]]
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| 705.88
| 705.88
| Perfect Fifth
| Perfect Fifth
| P5
| G
| G
|perfect 5th
|P5
| G
| G
| [[3/2]]
| [[3/2]]
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| 776.47
| 776.47
| Super Fifth/Minor Sixth
| Super Fifth/Minor Sixth
| m6
| Ab
| Ab
|minor 6th
|m6
| ^G
| ^G
| [[25/16]], [[14/9]], [[11/7]], [[52/33]], [[36/23]]
| [[25/16]], [[14/9]], [[11/7]], [[52/33]], [[36/23]]
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| 12
| 12
| 847.06
| 847.06
| Augmented Fifth/Neutral Sixth/ <br> Diminished Seventh
| Augmented Fifth/Neutral  
| ~6
Sixth/Diminished Seventh
| G#
| G#
|mid 6th
|~6
| vA
| vA
| [[13/8]], [[18/11]], [[23/14]]
| [[13/8]], [[18/11]], [[23/14]]
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| 917.65
| 917.65
| Major Sixth/Sub Seventh
| Major Sixth/Sub Seventh
| M6
| A
| A
|major 6th
|M6
| A
| A
| [[17/10]], [[22/13]],[[12/7]]
| [[17/10]], [[22/13]],[[12/7]]
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| 988.24
| 988.24
| Minor Seventh/Super Sixth
| Minor Seventh/Super Sixth
| m7
| Bb
| Bb
|minor 7th
|m7
| ^A
| ^A
| [[16/9]], [[7/4]], [[25/14]], [[44/25]], [[23/13]]
| [[16/9]], [[7/4]], [[25/14]], [[44/25]], [[23/13]]
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| 15
| 15
| 1058.82
| 1058.82
| Augmented Sixth/Neutral Seventh/ <br> Diminished Octave
| Augmented Sixth/Neutral
| ~7
Seventh/Diminished Octave
| A# <br> (Cb)
| A# <br> (Cb)
|mid 7th
|~7
| vB
| vB
| [[11/6]], [[24/13]], [[13/7]], [[46/25]]
| [[11/6]], [[24/13]], [[13/7]], [[46/25]]
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| 1129.41
| 1129.41
| Major Seventh/Sub Octave
| Major Seventh/Sub Octave
| M7
| B
| B
|major 7th
|M7
| B
| B
| [[25/13]], [[48/25]], [[64/33]], [[23/12]]
| [[25/13]], [[48/25]], [[64/33]], [[23/12]]
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| 1200.00
| 1200.00
| Perfect Octave
| Perfect Octave
| P8
| C
| C
|octave
|P8
| C
| C
| [[2/1]]
| [[2/1]]
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=== Selected just intervals by error ===
=== Selected just intervals by error ===
{| class="wikitable center-all"
! colspan="2" |
! prime 2
! prime 3
! prime 5
! prime 7
! prime 11
! prime 13
!prime 17
!prime 19
!prime 23
|-
! rowspan="2" | Error
! absolute ([[cent|¢]])
| 0
| +3.9
| -33.4
| +19.4
| +13.4
| +6.5
| -34.3
| -15.2
| +7.0
|-
! [[Relative error|relative]] (%)
| 0
| +5.6
| -47.3
| +27.5
| +19.0
| +9.2
| -48.7
| -21.5
| +9.9
|-
! colspan="2" | [[fifthspan]]
| 0
| +1
| -8
| -2
| -6
| +8
| -5
| -3
| +6
|}
==== 15-odd-limit mappings ====
==== 15-odd-limit mappings ====
The following table shows how [[15-odd-limit intervals]] are represented in 17edo (ordered by absolute error). Prime harmonics are in '''bold'''; inconsistent intervals are in ''italic''.  
The following table shows how [[15-odd-limit intervals]] are represented in 17edo (ordered by absolute error). Prime harmonics are in '''bold'''; inconsistent intervals are in ''italic''.  
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* [[User:CritDeathX/Sam's 17-note Well Temperament|Sam's 17-note Well Temperament]]
* [[User:CritDeathX/Sam's 17-note Well Temperament|Sam's 17-note Well Temperament]]
* [[User:FloraC/Flora's 17-note well temperament|Flora's 17-note well temperament]]
* [[User:FloraC/Flora's 17-note well temperament|Flora's 17-note well temperament]]
== Introductory materials ==
* [[SeventeenTheory]], an introduction to 17-EDO theory, through the eyes of the [[SeventeenTonePianoProject]].
* [http://anaphoria.com/Secor17puzzle.pdf The 17-tone Puzzle] by George Secor, another introduction into 17-EDO theory.
* [[17edo Solfege]]
* [[17edo tetrachords]]
* [http://microtonalismo.com/proyecto-xvii Proyect 17-Perú] {{forbidden}}


== Music ==
== Music ==

Revision as of 04:41, 9 December 2020

← 16edo 17edo 18edo →
Prime factorization 17
Step size 70.5882 ¢ 
Fifth 10\17 (705.882 ¢)
(semiconvergent)
Semitones (A1:m2) 2:1 (141.2 ¢ : 70.59 ¢)
Consistency limit 3
Distinct consistency limit 3

17 tone equal temperament, or 17-EDO, divides the octave in 17 equal steps, each 70.588 cents in size. It is the seventh prime EDO, following 13edo and coming before 19edo.

Theory

prime 2 prime 3 prime 5 prime 7 prime 11 prime 13 prime 17 prime 19 prime 23
Error absolute (¢) 0 +3.93 -33.4 +19.4 +13.4 +6.5 -34.3 -15.2 +7.0
relative (%) 0 +6 -47 +27 +19 +9 -49 -21 +10
nearest edomapping 17 10 5 14 8 12 1 4 9
fifthspan 0 +1 -8 -2 -6 +8 -5 -3 +6

17-EDO can plausibly be treated as a 2.3.25.7.11.13.23 subgroup temperament, for which it is quite accurate (though the 7-limit ratios are generally not as well-represented as those of the other integers). Because the 3, 7, 11, and 13 are all sharp, it adapts well to octave shrinking; 27edt (a variant of 17edo in which the octaves are flattened by ~2.5 cents) is a good alternative. Another one is 44ed6.

As a no-fives system, it is best used with timbres in which harmonic multiples of 5 are attenuated or absent. Also, the standard major chord (4:5:6) cannot be used since it includes the fifth harmonic.

Instead, the tonic chords of 17-EDO could be considered to be the tetrad 6:7:8:9 and its utonal inversion, the former of which is a subminor chord with added fourth, and the latter a supermajor chord with added second (resembling the mu chord of Steely Dan fame). These are realized in 17-EDO as 0-4-7-10 and 0-3-6-10, respectively. Both of these have distinct moods, and are stable and consonant, if somewhat more sophisticated than their classic 5-limit counterparts. To this group we could also add the 0-3-7-10 (which is a sus4 with added second, or sus2 with added fourth). These three chords comprise the three ways to divide the 17-EDO perfect fifth into two whole tones and one subminor third. Chromatic alterations of them also exist, for example, the 0-3-7-10 chord may be altered to 0-2-7-10 (which approximates 12:13:16:18) or 0-3-8-10 (which approximates 8:9:11:12). The 0-3-8-10 chord is impressive-sounding, resembling a sus4 but with even more tension; it resolves quite nicely to 0-3-6-10.

Intervals

Edo steps Cents Names of Intervals, extended

pythagorean note names

Ups and Downs Notation Approximate Ratios* Temperament(s) generated
0 0.00 Unison C unison P1 C 1/1
1 70.59 Super Unison/Minor Second Db
(B#)
minor 2nd m2 ^C 25/24, 26/25, 33/32, 24/23
2 141.18 Augmented Unison/Neutral Second C# mid 2nd ~2 vD 13/12, 12/11, 14/13, 25/23 Bleu
3 211.76 Major Second/Sub Third D major 2nd M2 D 9/8, 8/7, 28/25, 25/22, 26/23 Machine
4 282.35 Minor Third/Super Second Eb minor 3rd m3 ^D 13/11, 7/6 Huxley/Lovecraft
5 352.94 Augmented Second/Neutral

Third/Diminished Fourth

D#
(Fb)
mid 3rd ~3 vE 11/9, 16/13, 28/23 Maqamic/Hemif
6 423.53 Major Third/Sub Fourth E major 3rd M3 E 32/25, 9/7, 14/11, 33/26, 23/18 Skwares
7 494.12 Perfect Fourth F perfect 4th P4 F 4/3 Supra
8 564.71 Super Fourth/Diminshed Fifth Gb
(E#)
mid 4th,

diminished 5th

~4,

d5

^F 11/8, 18/13, 32/23 Progress
9 635.29 Augmented Fourth/Sub Fifth F# augmented 4th,

mid 5th

A4, ~5 vG 16/11, 13/9, 23/16 Progress
10 705.88 Perfect Fifth G perfect 5th P5 G 3/2 Supra
11 776.47 Super Fifth/Minor Sixth Ab minor 6th m6 ^G 25/16, 14/9, 11/7, 52/33, 36/23 Skwares
12 847.06 Augmented Fifth/Neutral

Sixth/Diminished Seventh

G# mid 6th ~6 vA 13/8, 18/11, 23/14 Maqamic/hemif
13 917.65 Major Sixth/Sub Seventh A major 6th M6 A 17/10, 22/13,12/7 Huxley
14 988.24 Minor Seventh/Super Sixth Bb minor 7th m7 ^A 16/9, 7/4, 25/14, 44/25, 23/13 Machine
15 1058.82 Augmented Sixth/Neutral

Seventh/Diminished Octave

A#
(Cb)
mid 7th ~7 vB 11/6, 24/13, 13/7, 46/25 Bleu
16 1129.41 Major Seventh/Sub Octave B major 7th M7 B 25/13, 48/25, 64/33, 23/12
17 1200.00 Perfect Octave C octave P8 C 2/1

* Ratios based on treating 17edo as a 2.3.7.11.13.23.25 subgroup

In 17edo, ups and downs can respectively be substituted with half-sharps and half-flats, since sharps and flats each span two edo steps. Using half-sharps and half-flats may be preferable for compatibility with the ups-and-downs notation in 34edo, in which an up or down respectively constitute a quarter-sharp or quarter-flat.

Combining ups and downs notation with color notation, qualities can be loosely associated with colors:

quality color monzo format examples
minor zo {a, b, 0, 1} 7/6, 7/4
" fourthward wa {a, b}, b < -1 32/27, 16/9
mid ilo {a, b, 0, 0, 1} 11/9, 11/6
" lu {a, b, 0, 0, -1} 12/11, 18/11
major fifthward wa {a, b}, b > 1 9/8, 27/16
" ru {a, b, 0, -1} 9/7, 12/7

Chord Names

All 17edo chords can be named using ups and downs. Here are the zo, ilo and ru triads:

color of the 3rd JI chord notes as edosteps notes of C chord written name spoken name
zo 6:7:9 0-4-10 C Eb G Cm C minor
ilo 18:22:27 0-5-10 C vE G C~ C mid
ru 14:18:21 0-6-10 C E G C C major or C

Alterations are always enclosed in parentheses, additions never are. An up, down or mid immediately after the chord root affects the 3rd, 6th, 7th, and/or the 11th (every other note of a stacked-3rds chord 6-1-3-5-7-9-11-13).

0-4-9 = C Eb vG = Cm(v5) = C minor down-five

0-5-9 = C vE vG = C~(v5) = C mid down-five

0-6-11 = C E ^G = C(^5) = C up-five

0-4-10-14 = C Eb G Bb = Cm7 = C minor seven

0-5-10-14 = C vE G Bb = C~,7 = C mid add seven

0-6-10-15 = C E G vB = C,~7 = C add mid-seven

0-5-10-15 = C vE G vB = C~7 = C mid-seven

For a more complete list, see Ups and Downs Notation - Chords and Chord Progressions.

Just approximation

Selected just intervals by error

15-odd-limit mappings

The following table shows how 15-odd-limit intervals are represented in 17edo (ordered by absolute error). Prime harmonics are in bold; inconsistent intervals are in italic.

Direct mapping (even if inconsistent)
Interval, complement Error (abs, ¢)
18/13, 13/9 1.324
13/12, 24/13 2.604
4/3, 3/2 3.927
11/9, 18/11 5.533
14/11, 11/7 6.021
16/13, 13/8 6.531
13/11, 22/13 6.857
9/8, 16/9 7.855
12/11, 11/6 9.461
9/7, 14/9 11.555
14/13, 13/7 12.878
11/8, 16/11 13.388
7/6, 12/7 15.482
7/5, 10/7 17.806
8/7, 7/4 19.409
15/14, 28/15 21.734
11/10, 20/11 23.828
15/11, 22/15 27.755
10/9, 9/5 29.361
16/15, 15/8 29.445
13/10, 20/13 30.685
6/5, 5/3 33.288
5/4, 8/5 33.373
15/13, 26/15 34.612
Patent val mapping
Interval, complement Error (abs, ¢)
18/13, 13/9 1.324
13/12, 24/13 2.604
4/3, 3/2 3.927
11/9, 18/11 5.533
14/11, 11/7 6.021
16/13, 13/8 6.531
13/11, 22/13 6.857
9/8, 16/9 7.855
12/11, 11/6 9.461
9/7, 14/9 11.555
14/13, 13/7 12.878
11/8, 16/11 13.388
7/6, 12/7 15.482
8/7, 7/4 19.409
16/15, 15/8 29.445
5/4, 8/5 33.373
15/13, 26/15 35.976
6/5, 5/3 37.300
13/10, 20/13 39.904
10/9, 9/5 41.227
15/11, 22/15 42.833
11/10, 20/11 46.760
15/14, 28/15 48.855
7/5, 10/7 52.782

Selected 13-limit intervals

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Temperament measures

The following table shows TE temperament measures (RMS normalized by the rank) of 17et.

3-limit 7-limit no-5 11-limit no-5 13-limit no-5
Octave stretch (¢) -1.24 -3.13 -3.31 -3.00
Error absolute (¢) 1.24 2.85 2.49 2.31
relative (%) 1.76 4.05 3.54 3.28
  • 17et has a lower relative error than any previous ETs in the no-5 11- and 13-limit. The next ET that does better in these subgroups is 41 and 207, respectively.

Commas

17 EDO tempers out the following commas. (Note: This assumes val 17 27 39 48 59 63], cent values ​​rounded to 5 digits.)

Prime
Limit
Comma Monzo Cents Color Name Name(s)
3 [27 -17 66.765 Sasawa 17-comma
5 25/24 [-3 -1 2 70.762 Yoyo Chromatic semitone, dicot comma
" 32805/32768 [-15 8 1 1.9537 Layo Schisma
7 525/512 [-9 1 2 1 43.408 Zoyoyo Avicennma, Avicennma's enharmonic diesis
" 64/63 [6 -2 0 -1 27.264 Ru Septimal comma, Archytas' comma, Leipziger Komma
" 245/243 [0 -5 1 2 14.191 Zozoyo Sensamagic
" 1728/1715 [6 3 -1 -3 13.074 Triru-agu Orwellisma, orwell comma
" [-6 -8 2 5 1.1170 Quinzo-ayoyo Wizma
11 99/98 [-1 2 0 -2 1 17.576 Loruru Mothwellsma
" 896/891 [7 -4 0 1 -1 9.6880 Saluzo Pentacircle
" 243/242 [-1 5 0 0 -2 7.1391 Lulu Rastma
" 385/384 [-7 -1 1 1 1 4.5026 Lozoyo Keenanisma
13 1352/1331 [3 0 0 0 -3 2 27.101 Bithotrilu Lovecraft comma

Note that despite their relatively large size, the 17-comma, the avicennma and the chromatic semitone are all tempered out by the 13-limit patent val, as stated.

Scales

Temperaments

Rank-two temperaments

Well temperaments

Introductory materials

Music

Scores

Sound files

Instruments

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17P1050829r.JPG