In music, **19 equal temperament**, called 19-TET, 19-[[xenharmonic/EDO|EDO]], or 19-ET, is the scale derived by dividing the [[xenharmonic/octave|octave]] into 19 [[xenharmonic/equal|equal]]ly large steps. Each step represents a frequency ratio of the 19th root of 2, or 63.16 [[xenharmonic/cent|cents]]. It is the 8th [[xenharmonic/prime numbers|prime]] edo, following [[xenharmonic/17edo|17edo]] and coming before [[xenharmonic/23edo|23edo]].
== History ==
Interest in this tuning system goes back to the sixteenth century, when composer Guillaume Costeley used it in his chanson [[Seigneur Dieu ta pitié]] of 1558. Costeley understood and desired the circulating aspect of this tuning, which he defined as dividing the just major second into three approximately equal parts. Costeley had other compositions that made use of intervals, such as the diminished third, which have a meaningful context in 19edo, but not in other tuning systems contemporary with the work.
Interest in this tuning system goes back to the sixteenth century, when composer Guillaume Costeley used it in his chanson [[Seigneur Dieu ta pitié]] of 1558. Costeley understood and desired the circulating aspect of this tuning; in 1577 music theorist Francisco de Salinas in effect proposed it. Salinas discussed [[xenharmonic/1-3 Syntonic Comma Meantone|1/3-comma meantone]], in which the fifth is of size 694.786 cents; the fifth of 19-et is 694.737, which is only a twentieth of a cent flatter. Salinas suggested tuning nineteen tones to the octave to this tuning, which fails to close by less than a cent, so that his suggestion is effectively 19-et. In the nineteenth century mathematician and music theorist Wesley Woolhouse proposed it as a more practical alternative to meantone tunings he regarded as better, such as [[xenharmonic/50edo|50 equal temperament]] ([[http://sonic-arts.org/monzo/woolhouse/essay.htm|summary of Woolhouse's essay]]).
In 1577, music theorist Francisco de Salinas proposed [[1/3-comma meantone]], in which the fifth is 694.786{{c}}; the fifth of 19edo is 694.737{{c}}, which is only a twentieth of a cent flatter. Salinas suggested tuning nineteen tones to the octave to this tuning, which comes within less than one cent of closing exactly, so that his suggestion is effectively 19edo.
==As an approximation of other temperaments==
In 1835, mathematician and music theorist Wesley Woolhouse proposed it as a more practical alternative to meantone tunings he regarded as better, such as [[50edo|50 equal temperament]] ([http://www.tonalsoft.com/sonic-arts/monzo/woolhouse/essay.htm summary of Woolhouse's essay]).
The most salient characteristic of 19-et is that, having an almost just minor third and perfect fifths and major thirds about seven cents narrow, it serves as a good tuning for [[xenharmonic/Meantone family|meantone]] temperament. It is also a suitable for [[xenharmonic/Regular Temperaments#magic|magic/muggles]] temperament, because five of its major thirds are equivalent to one of its //twelfths.// For both of these there are more optimal tunings: the fifth of 19-et is flatter than the usual for meantone, and a more accurate approximation is [[xenharmonic/31edo|31 equal temperament]]. Similarly, the generating interval of magic temperament is a major third, and again 19-et's is flatter; [[xenharmonic/41edo|41 equal temperament]] more closely matches it. It does make for a good tuning for muggles, which in 19et is the same as magic.
== Theory ==
19edo is the second edo, after [[12edo]], which is able to approximate [[5-limit]] intervals and chords with tolerable accuracy (unless you count [[15edo]], which has a 18-[[cent]]-sharp fifth). Having an almost just minor third and perfect fifths and major thirds about 7 cents flat, it serves as a good tuning for [[meantone]]. Unlike 12edo, where [[enharmonic]] notes are conflated, 19edo distinguishes them, and differs from [[17edo]] in that its [[diatonic semitone]] is wider than the [[chromatic semitone]], rather than narrower. In fact, it is nearly identical to the enharmonic scale of [[1/3-comma meantone]], and can be considered a closed form thereof.
However, for all of these 19-et has the practical advantage of requiring fewer pitches, which makes physical realizations of it easier to build. (Many 19-et instruments have been built.) 19-et is in fact the second equal temperament, after 12-et which is able to deal with [[xenharmonic/Harmonic Limit|5-limit]] music in a tolerable manner, and is the fifth (after 12) [[xenharmonic/The Riemann Zeta Function and Tuning#Zeta%20EDO%20lists|zeta integral edo]]. It is less successful with [[xenharmonic/7-limit|7-limit]] (but still better than 12-et), as it eliminates the distinction between a septimal minor third ([[xenharmonic/7_6|7/6]]), and a septimal whole tone ([[xenharmonic/8_7|8/7]]). 19-EDO also has the advantage of being excellent for negri, keemun, godzilla, magic/muggles and triton/liese, and fairly decent for sensi. Keemun and Negri are of particular note for being very simple 7-limit temperaments, with their MOS scales in 19-EDO offering a great abundance of septimal tetrads. The [[xenharmonic/Graham complexity|Graham complexity]] of a 7-limit tetrad is 6 for keemun, 7 for negri, 8 for godzilla, 10 for meantone/flattone, 11 for triton, 12 for magic/muggles and 13 for sensi.
It is less successful in the [[7-limit]] as it conflates the septimal subminor third ([[7/6]]) with the septimal whole tone ([[8/7]]), but it is still better than 12edo overall.
Being a zeta integral tuning, the 13-limit is represented relatively well, and practically [[19edo|19-edo]] can be used //adaptively// on instruments which are allowing you to bend notes up: by different amounts, the 3rd, 5th, 7th and 13th harmonics are all tuned flat. The same cannot be said of 12edo, in which the 5th, 7th and 11th are - not only farther than they are in 19, but fairly sharp already.
=== Prime harmonics ===
{{Harmonics in equal|19|columns=12}}
==Intervals and linear temperaments==
=== As an approximation of other temperaments ===
[[xenharmonic/List of 19et rank two temperaments by badness|List of 19et rank two temperaments by badness]]
Besides meantone, 19edo is also suitable for [[magic]]/[[muggles]] temperament, because five of its major thirds are equivalent to one of its twelfths. Its 7-step supermajor third can be used for [[sensi]], whose generator is a very sharp major third, two of which make an approximate 5/3 major sixth.
[[List of 19et rank two temperaments by complexity]]
[[List of edo-distinct 19et rank two temperaments]]
Since 19 is prime, all rank two temperaments in 19edo have one period per octave. Therefore you can make a correspondence between intervals and the linear temperaments they generate.
For all of these there are more optimal tunings: the fifth of 19edo is flatter than the usual for meantone, and [[31edo]] is more optimal. Similarly, the generating interval of magic temperament is a major third, and again 19edo's is flatter; [[41edo]] more closely matches it. It does make for a good tuning for muggles, but in 19edo it is the same as magic. Finally, 19edo can be used as a tuning for sensi, though [[46edo]] provides a better sensi tuning.
||~ Degrees of 19edo ||~ Solfege ||~ Cents value ||~ Ratios* ||~ Generator for ||
|| 18 || da || 1136.84 || || Unicorn/rhinocerus ||
*based on treating 19-EDO as a 2.3.5.7.13 subgroup temperament; other approaches are possible.
==Commas==
However, for all of these 19edo has the practical advantage of requiring fewer pitches, which makes it easier to implement in physical instruments, and many 19edo instruments have been built. 19edo also has the advantage of being excellent for [[negri]], [[keemun]], [[godzilla]], muggles, and [[triton]]/[[liese]]. Keemun and negri are of particular note for being very simple 7-limit temperaments, with their [[mos scale]]s in 19edo offering a great abundance of septimal tetrads. The [[Graham complexity]] of the [[4:5:6:7|7-odd-limit tetrad]] is 6 for keemun, 7 for negri, 8 for godzilla, 10 for meantone, 11 for triton, 12 for magic/muggles, and 13 for sensi.
19 EDO [[xenharmonic/tempering out|tempers out]] the following [[xenharmonic/comma|comma]]s. (Note: This assumes the [[xenharmonic/val|val]] < 19 30 44 53 66 70 |.)
||~ Comma ||~ Monzo ||~ Value (Cents) ||~ Name 1 ||~ Name 2 ||~ Name 3 ||
Because 19edo's 5-limit chords are more blended and concordant than those of 12edo, it can be a much better candidate for using alternate forms of harmony such as quartal, secundal, and poly chords. [[William Lynch]] suggests the use of seventh chords of various types to be the fundamental sonorities with a triad deemed as incomplete. Higher extensions involving the 7th harmonic as well as other non-diatonic chord extensions which tend to clash in 12edo blend much better in 19edo.
==See also==
In addition, [[Joseph Yasser]] talks about the idea of a 12-tone supra-diatonic scale where the 7-tone major scale in 19edo becomes akin to the pentatonic of western music; as it would sound to a future generation, ambiguous and not tonally fortified. As paraphrased "A system in which the undeniable laws of tonal gravity exist, yet in a much more complex tonal universe." Yasser believed that music would eventually move to a 19-tone system with a 12-note supra-diatonic scale would become the standard. While this has yet to happen, Yasser's concept of supra-diatonicity is intriguing and worth exploring for those wanting to extend tonality without sounding too alien.
[[How to tune a 19edo guitar by ear]]
==Articles==
* [[http://sonic-arts.org/darreg/case.htm|A Case For Nineteen]] by [[xenharmonic/Ivor Darreg|Ivor Darreg]] [[http://www.webcitation.org/5xZzBtDGF|Permalink]]
19edo also closely approximates most of the intervals of [[Bozuji tuning]], a 21st century tuning based on Gioseffo Zarlino's approach to just intonation. with most of the adjacent diatonic diminished and augmented intervals of Bozuji tuning represented enharmonically by one interval in 19edo.
* [[http://www.microstick.net/nineteenarticle.htm|Nineteen for the Nineties]] by Ivor Darreg
* [[http://qcpages.qc.edu/%7Ehowe/articles/19-Tone%20Theory.html|19-Tone Theory and Applications]] by Hubert S. Howe Jr. [[http://www.webcitation.org/5xbMKVaqa|Permalink]]
* [[http://sethares.engr.wisc.edu/tet19/guitarchords19.html|Tunings for 19 Tone Equal Tempered Guitar]] by William A. Sethares [[http://www.webcitation.org/5xeCbEPZ0|Permalink]]
* [[http://www.n-ism.org/Projects/microtonalism.php|Microtonalism]] by Bailey, Morrison, Pearson and Parncutt [[http://www.webcitation.org/5xeDFQDvn|Permalink]]
* [[http://tonalsoft.com/enc/number/19edo.aspx|19-tone equal-temperament and 1/3-comma meantone - Encyclopedia of Microtonal Music Theory]] [[http://tonalsoft.com/enc/number/19edo.aspx|Permalink]]
* [[http://mtg.redkeylabs.com/index.php?topic=6.0|Forum Discussion with some 19-EDO xenharmonic scales Hanson (Keemun), Liese, Negri, Magic, Semaphore, Sensi played on guitar]].
* [[http://www.ronsword.com/books.html|Enneadecaphonic Scales for Guitar]] by [[xenharmonic/Ron Sword|Ron Sword]]
==References==
Due to the narrow whole tones and wide diatonic semitones, 19edo's diatonic scale tends to sound somewhat dull compared to 12edo, but the pentatonic scale is said by many to sound much more expressive owing to the significantly larger contrast between the narrow whole tone and wide minor third. While 12edo has an expressive diatonic and dull pentatonic, the reverse is true in 19. Pentatonicism thus becomes more important in 19edo, and one option is to use the pentatonic scale as a sort of "super-chord", with "chord progressions" being modulations between pentatonic subsets of the superdiatonic scale.
Bucht, Saku and Huovinen, Erkki, //Perceived consonance of harmonic intervals in 19-tone equal temperament//, CIM04_proceedings.
The no-11's 13-limit is represented relatively well and consistently. 19edo's negri, sensi and godzilla scales have many 13-limit chords. (You can think of the Sensi[8] [[3L 5s]] mos scale as 19edo's answer to the diminished scale. Both are made of two diminished seventh chords, but Sensi[8] gives you additional ratios of 7 and 13.) Its diminished fifth is also a very accurate approximation of the 23rd harmonic, being only 3.3{{c}} off [[23/16]].
Moyen-Age et Renaissance, Tome III (1955), pp. 213-261.
19 note per octave Ibanez conversion by Brad Smith (Indianapolis)
Practically 19edo can be used ''adaptively'' on instruments which allow you to bend notes up: by different amounts, the 3rd, 5th, 7th, and 13th harmonics are all tuned flat. This is in contrast to 12edo, where this is not possible since the 5th and 7th harmonics are not only much farther from just than they are in 19edo, but fairly sharp already.
Another option would be to use [[octave stretching]], which has similar benefits to adaptive use, but it also works for fixed-pitch Instruments. For more on that see the [[19edo#Octave stretch or compression|section on octave stretch]].
[[http://music.columbia.edu/%7Echris/sand.html|Sand]] by [[xenharmonic/Christopher Bailey|Christopher Bailey]]
<span class="ymp-btn-page-play ymp-media-1ec26b280d7788ac0e790719d577a218"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link">//[[http://works.music.columbia.edu/%7Echris/19mix1.mp3|Walking Down the Hillside at Cortona, and Seeing its Towers Rise Before Me]]//</span></span></span></span> </span>by Christopher Bailey
////[[http://micro.soonlabel.com/gene_ward_smith/misc/Guillaume%20Costeley%20-%20Seigneur%20Dieu%20ta%20piti%e9.mp3|Seigneur Dieu ta pitié]]//// by Guillaume Costeley
////[[http://micro.soonlabel.com/0-hosted-albums/ivor/02%20Prelude%202%20for%2019%20tone%20guitar.mp3|Prelude 2 for 19 tone guitar]]//// by [[Ivor Darreg]]
////[[http://archive.org/download/LimpOffToSchool/LimpOffToSchool19tet.mp3|Limp Off to School]]//// by [[xenharmonic/John Starrett|John Starrett]].
<span class="ymp-btn-page-play ymp-media-e5a2a3d148bc1b07acdba10ca90219c7"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link">////[[http://clones.soonlabel.com/public/micro/gene_ward_smith/Others/Khramov/betelgeuse.mp3|The Light Of My Betelgeuse]]////</span></span></span></span></span> by [[xenharmonic/Mykhaylo Khramov|Mykhaylo Khramov]]
////[[http://archive.org/download/ElementalsFor2PianosIn19EqualTemperament/01.Undines.mp3|Undines]]////, ////[[http://archive.org/download/ElementalsFor2PianosIn19EqualTemperament/02.Sylphs.mp3|Sylphs]]////, ////[[http://archive.org/download/ElementalsFor2PianosIn19EqualTemperament/03.Gnomes.mp3|Gnomes]]////, and ////[[http://archive.org/download/ElementalsFor2PianosIn19EqualTemperament/04.Salamanders.mp3|Salamanders]]//// by Jon Lyle Smith
[[http://archive.org/details/AnotherAireForLute|Another Aire For Lute]] by Jon Lyle Smith
A number of compositions that were perfomed at the [[http://midwestmicrofest.org/concerts.html|midwestmicrofest concert in 2007]]
Fanfare in 19-note Equal Tuning by Easley Blackwood
//[[http://www.uvnitr.cz/flaoyg/flao_yg/zvire.mp3|Zvíře]]// by [[http://www.uvnitr.cz/flaoyg/flao_yg/zvire.html|Milan Guštar]]
[[http://www.ziaspace.com/ZIA/sections/music.html|19tet downloadable mp3s by ZIA, Elaine Walker and D.D.T.]]
[[@http://chrisvaisvil.com/?p=865|Forgetting Even Her Beauty blog]] <span class="ymp-btn-page-play ymp-media-7cdb4644c05849d85c1a04ed2a07a5a7"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link">////[[http://micro.soonlabel.com/19-ET/daily20110516-19-forgetting_even_her_beauty.mp3|play Forgetting Even Her Beauty]]////</span></span></span></span> </span>by [[xenharmonic/Chris Vaisvil|Chris Vaisvil]]
[[@http://chrisvaisvil.com/?p=855|19 Black Hawks for Osama blog]] <span class="ymp-media-3badeb9b3b5a5768a5e43cea7e10b377 ymp-btn-page-play"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover ywp-page-img-link">////[[http://www.youtube.com/watch?v=gGO0R381HQs|play video for 19 Black Hawks for Osama]]//// </span></span></span></span> </span>by Chris Vaisvil
[[@http://chrisvaisvil.com/?p=823|Summer Song blog]] <span class="ymp-media-44691c8e07e030770b33e146e0d88212 ymp-btn-page-play"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link">////[[http://micro.soonlabel.com/19-ET/daily20110501-19-summer_song_mix3.mp3|play Summer Song]]////</span></span></span></span> </span>by Trevor (The TwoRegs) and Norm Harris and Chris Vaisvil
[[@http://chrisvaisvil.com/?p=820|19 ImprovFridays blog]] <span class="ymp-btn-page-play ymp-media-c6d81d29a5290997eac85574c62b39e3"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover ywp-page-img-link">////[[http://www.youtube.com/watch?v=-KaRXFoYwT4|play video of performance of 19 ImprovFridays]]//// </span></span></span></span> </span>by Chris Vaisvil
[[@http://chrisvaisvil.com/?p=800|The World has Changed blog]] <span class="ymp-media-d1cc76332b281044aecd4287b683de9d ymp-btn-page-play"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link">////[[http://micro.soonlabel.com/19-ET/daily20110429-19edo-the_world_has_changed3.mp3|play The World has Changed]]////</span></span></span></span> </span>by Chris Vaisvil
[[http://chrisvaisvil.com/?p=883|jjj]] <span class="ymp-btn-page-play ymp-media-35bea9630e48d0842ee9259bac028257"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link">////[[http://micro.soonlabel.com/19-ET/daily20110523-19take2.mp3|play]]////</span></span></span></span></span> by Chris Vaisvil
[[http://soundcloud.com/omega9/chip-chamber|Now listen! Pitch!]] //[[http://micro.soonlabel.com/gene_ward_smith/Others/Omega9/Now%20listen%21%20Pitch%21.mp3|play]]// by Omega9
[[https://www.youtube.com/watch?v=mlvme3ukPLE|Cordas (19-edo version)]] //[[http://micro.soonlabel.com/gene_ward_smith/Others/Omega9/Omega9%20-%20Cordas.mp3|play]]// by Omega9
////[[http://www.youtube.com/watch?v=DSOGF4gDYu8|A Piece in 19edo]]//// by Omega9
[[http://soundcloud.com/omega9/a-piece-in-19edo-version-3|A Piece in 19edo (ver.3)]] //[[http://micro.soonlabel.com/gene_ward_smith/Others/Omega9/Omega9%20-%20A%20Piece%20in%2019edo.mp3|play]]// by Omega9
<span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link">////[[http://micro.soonlabel.com/gene_ward_smith/Others/Meneghin/WTC2-24/19-edo-A-Prelude.mp3|Bach’s Prelude number 24 from Well Tempered Clavier, Book II]]////</span></span></span>
<span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link">////[[http://micro.soonlabel.com/gene_ward_smith/Others/Meneghin/WTC2-24/19-edo-B-Fugue.mp3|Bach’s Fugue number 24 from Well Tempered Clavier, Book II]]////</span></span></span>
In music, <strong>19 equal temperament</strong>, called 19-TET, 19-<a class="wiki_link" href="http://xenharmonic.wikispaces.com/EDO">EDO</a>, or 19-ET, is the scale derived by dividing the <a class="wiki_link" href="http://xenharmonic.wikispaces.com/octave">octave</a> into 19 <a class="wiki_link" href="http://xenharmonic.wikispaces.com/equal">equal</a>ly large steps. Each step represents a frequency ratio of the 19th root of 2, or 63.16 <a class="wiki_link" href="http://xenharmonic.wikispaces.com/cent">cents</a>. It is the 8th <a class="wiki_link" href="http://xenharmonic.wikispaces.com/prime%20numbers">prime</a> edo, following <a class="wiki_link" href="http://xenharmonic.wikispaces.com/17edo">17edo</a> and coming before <a class="wiki_link" href="http://xenharmonic.wikispaces.com/23edo">23edo</a>.<br />
<br />
Interest in this tuning system goes back to the sixteenth century, when composer Guillaume Costeley used it in his chanson <a class="wiki_link" href="/Seigneur%20Dieu%20ta%20piti%C3%A9">Seigneur Dieu ta pitié</a> of 1558. Costeley understood and desired the circulating aspect of this tuning; in 1577 music theorist Francisco de Salinas in effect proposed it. Salinas discussed <a class="wiki_link" href="http://xenharmonic.wikispaces.com/1-3%20Syntonic%20Comma%20Meantone">1/3-comma meantone</a>, in which the fifth is of size 694.786 cents; the fifth of 19-et is 694.737, which is only a twentieth of a cent flatter. Salinas suggested tuning nineteen tones to the octave to this tuning, which fails to close by less than a cent, so that his suggestion is effectively 19-et. In the nineteenth century mathematician and music theorist Wesley Woolhouse proposed it as a more practical alternative to meantone tunings he regarded as better, such as <a class="wiki_link" href="http://xenharmonic.wikispaces.com/50edo">50 equal temperament</a> (<a class="wiki_link_ext" href="http://sonic-arts.org/monzo/woolhouse/essay.htm" rel="nofollow">summary of Woolhouse's essay</a>).<br />
<br />
<!-- ws:start:WikiTextHeadingRule:3:&lt;h2&gt; --><h2 id="toc1"><a name="Theory-As an approximation of other temperaments"></a><!-- ws:end:WikiTextHeadingRule:3 -->As an approximation of other temperaments</h2>
<br />
The most salient characteristic of 19-et is that, having an almost just minor third and perfect fifths and major thirds about seven cents narrow, it serves as a good tuning for <a class="wiki_link" href="http://xenharmonic.wikispaces.com/Meantone%20family">meantone</a> temperament. It is also a suitable for <a class="wiki_link" href="http://xenharmonic.wikispaces.com/Regular%20Temperaments#magic">magic/muggles</a> temperament, because five of its major thirds are equivalent to one of its <em>twelfths.</em> For both of these there are more optimal tunings: the fifth of 19-et is flatter than the usual for meantone, and a more accurate approximation is <a class="wiki_link" href="http://xenharmonic.wikispaces.com/31edo">31 equal temperament</a>. Similarly, the generating interval of magic temperament is a major third, and again 19-et's is flatter; <a class="wiki_link" href="http://xenharmonic.wikispaces.com/41edo">41 equal temperament</a> more closely matches it. It does make for a good tuning for muggles, which in 19et is the same as magic.<br />
<br />
However, for all of these 19-et has the practical advantage of requiring fewer pitches, which makes physical realizations of it easier to build. (Many 19-et instruments have been built.) 19-et is in fact the second equal temperament, after 12-et which is able to deal with <a class="wiki_link" href="http://xenharmonic.wikispaces.com/Harmonic%20Limit">5-limit</a> music in a tolerable manner, and is the fifth (after 12) <a class="wiki_link" href="http://xenharmonic.wikispaces.com/The%20Riemann%20Zeta%20Function%20and%20Tuning#Zeta%20EDO%20lists">zeta integral edo</a>. It is less successful with <a class="wiki_link" href="http://xenharmonic.wikispaces.com/7-limit">7-limit</a> (but still better than 12-et), as it eliminates the distinction between a septimal minor third (<a class="wiki_link" href="http://xenharmonic.wikispaces.com/7_6">7/6</a>), and a septimal whole tone (<a class="wiki_link" href="http://xenharmonic.wikispaces.com/8_7">8/7</a>). 19-EDO also has the advantage of being excellent for negri, keemun, godzilla, magic/muggles and triton/liese, and fairly decent for sensi. Keemun and Negri are of particular note for being very simple 7-limit temperaments, with their MOS scales in 19-EDO offering a great abundance of septimal tetrads. The <a class="wiki_link" href="http://xenharmonic.wikispaces.com/Graham%20complexity">Graham complexity</a> of a 7-limit tetrad is 6 for keemun, 7 for negri, 8 for godzilla, 10 for meantone/flattone, 11 for triton, 12 for magic/muggles and 13 for sensi.<br />
<br />
Being a zeta integral tuning, the 13-limit is represented relatively well, and practically <a class="wiki_link" href="/19edo">19-edo</a> can be used <em>adaptively</em> on instruments which are allowing you to bend notes up: by different amounts, the 3rd, 5th, 7th and 13th harmonics are all tuned flat. The same cannot be said of 12edo, in which the 5th, 7th and 11th are - not only farther than they are in 19, but fairly sharp already.<br />
<br />
<!-- ws:start:WikiTextHeadingRule:5:&lt;h2&gt; --><h2 id="toc2"><a name="Theory-Intervals and linear temperaments"></a><!-- ws:end:WikiTextHeadingRule:5 -->Intervals and linear temperaments</h2>
<a class="wiki_link" href="http://xenharmonic.wikispaces.com/List%20of%2019et%20rank%20two%20temperaments%20by%20badness">List of 19et rank two temperaments by badness</a><br />
<a class="wiki_link" href="/List%20of%2019et%20rank%20two%20temperaments%20by%20complexity">List of 19et rank two temperaments by complexity</a><br />
<a class="wiki_link" href="/List%20of%20edo-distinct%2019et%20rank%20two%20temperaments">List of edo-distinct 19et rank two temperaments</a><br />
<br />
Since 19 is prime, all rank two temperaments in 19edo have one period per octave. Therefore you can make a correspondence between intervals and the linear temperaments they generate.<br />
=== Subsets and supersets ===
19edo is the 8th [[prime edo]], following [[17edo]] and preceding [[23edo]]. As such, it does not contain any nontrivial subset edos, though it contains [[19ed4]].
<table class="wiki_table">
[[38edo]], which doubles 19edo, provides an approximation of harmonic 11 that works well with the flat tendency of its 5-limit mapping. See [[undevigintone]]. [[57edo]] effectively corrects the harmonic 7 to just, although it is [[76edo]] that fits the best. See [[meanmag]].
*based on treating 19-EDO as a 2.3.5.7.13 subgroup temperament; other approaches are possible.<br />
=== Miscellaneous properties ===
<br />
19edo has the flattest possible fifth of any edo that can possibly be [[diamond monotone]] in the [[15-odd-limit]]. Using 11\19 as the fifth, the sharpest possible mapping of [[5/4]] where [[10/9]] is no greater than [[9/8]] is 6\19, so the sharpest possible [[15/8]] is 17\19. Here [[16/15]] is a quarter of [[4/3]] (as in any [[negri]] tuning), so [[15/14]], [[14/13]], and [[13/12]] must all be equated with [[16/15]] to 2\19 for them to be monotone in size. If the fifth were any flatter, 5/4 and 15/8 would have to be flatter, and 16/15 would have to be sharper, so diamond monotone in the 15-odd-limit becomes impossible. 19edo is, in fact, diamond monotone in the 15-odd-limit, and even the [[17-odd-limit]] (see [[Monotonicity limits of small EDOs]]). The sharpest fifth where 15-odd-limit is possible is [[37edo#Miscellaneous properties|22\37]].
<ul><li><a class="wiki_link_ext" href="http://sonic-arts.org/darreg/case.htm" rel="nofollow">A Case For Nineteen</a> by <a class="wiki_link" href="http://xenharmonic.wikispaces.com/Ivor%20Darreg">Ivor Darreg</a> <a class="wiki_link_ext" href="http://www.webcitation.org/5xZzBtDGF" rel="nofollow">Permalink</a></li><li><a class="wiki_link_ext" href="http://www.microstick.net/nineteenarticle.htm" rel="nofollow">Nineteen for the Nineties</a> by Ivor Darreg</li><li><a class="wiki_link_ext" href="http://qcpages.qc.edu/%7Ehowe/articles/19-Tone%20Theory.html" rel="nofollow">19-Tone Theory and Applications</a> by Hubert S. Howe Jr. <a class="wiki_link_ext" href="http://www.webcitation.org/5xbMKVaqa" rel="nofollow">Permalink</a></li><li><a class="wiki_link_ext" href="http://sethares.engr.wisc.edu/tet19/guitarchords19.html" rel="nofollow">Tunings for 19 Tone Equal Tempered Guitar</a> by William A. Sethares <a class="wiki_link_ext" href="http://www.webcitation.org/5xeCbEPZ0" rel="nofollow">Permalink</a></li><li><a class="wiki_link_ext" href="http://www.n-ism.org/Projects/microtonalism.php" rel="nofollow">Microtonalism</a> by Bailey, Morrison, Pearson and Parncutt <a class="wiki_link_ext" href="http://www.webcitation.org/5xeDFQDvn" rel="nofollow">Permalink</a></li><li><a class="wiki_link_ext" href="http://tonalsoft.com/enc/number/19edo.aspx" rel="nofollow">19-tone equal-temperament and 1/3-comma meantone - Encyclopedia of Microtonal Music Theory</a> <a class="wiki_link_ext" href="http://tonalsoft.com/enc/number/19edo.aspx" rel="nofollow">Permalink</a></li><li><a class="wiki_link_ext" href="http://mtg.redkeylabs.com/index.php?topic=6.0" rel="nofollow">Forum Discussion with some 19-EDO xenharmonic scales Hanson (Keemun), Liese, Negri, Magic, Semaphore, Sensi played on guitar</a>.</li><li><a class="wiki_link_ext" href="http://www.ronsword.com/books.html" rel="nofollow">Enneadecaphonic Scales for Guitar</a> by <a class="wiki_link" href="http://xenharmonic.wikispaces.com/Ron%20Sword">Ron Sword</a></li></ul><br />
Bucht, Saku and Huovinen, Erkki, <em>Perceived consonance of harmonic intervals in 19-tone equal temperament</em>, CIM04_proceedings.<br />
<a class="wiki_link_ext" href="http://music.columbia.edu/%7Echris/sand.html" rel="nofollow">Sand</a> by <a class="wiki_link" href="http://xenharmonic.wikispaces.com/Christopher%20Bailey">Christopher Bailey</a><br />
| 6/5, 9/5
<span class="ymp-btn-page-play ymp-media-1ec26b280d7788ac0e790719d577a218"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><em><a class="wiki_link_ext" href="http://works.music.columbia.edu/%7Echris/19mix1.mp3" rel="nofollow">Walking Down the Hillside at Cortona, and Seeing its Towers Rise Before Me</a></em></span></span></span></span> </span>by Christopher Bailey<br />
<a class="wiki_link_ext" href="http://micro.soonlabel.com/gene_ward_smith/misc/Guillaume%20Costeley%20-%20Seigneur%20Dieu%20ta%20piti%e9.mp3" rel="nofollow">Seigneur Dieu ta pitié</a> by Guillaume Costeley<br />
| yo
<a class="wiki_link_ext" href="http://micro.soonlabel.com/0-hosted-albums/ivor/02%20Prelude%202%20for%2019%20tone%20guitar.mp3" rel="nofollow">Prelude 2 for 19 tone guitar</a> by <a class="wiki_link" href="/Ivor%20Darreg">Ivor Darreg</a><br />
<a class="wiki_link_ext" href="http://archive.org/download/LimpOffToSchool/LimpOffToSchool19tet.mp3" rel="nofollow">Limp Off to School</a> by <a class="wiki_link" href="http://xenharmonic.wikispaces.com/John%20Starrett">John Starrett</a>.<br />
| 9/8, 27/16
<span class="ymp-btn-page-play ymp-media-e5a2a3d148bc1b07acdba10ca90219c7"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><a class="wiki_link_ext" href="http://clones.soonlabel.com/public/micro/gene_ward_smith/Others/Khramov/betelgeuse.mp3" rel="nofollow">The Light Of My Betelgeuse</a></span></span></span></span></span> by <a class="wiki_link" href="http://xenharmonic.wikispaces.com/Mykhaylo%20Khramov">Mykhaylo Khramov</a><br />
|-
<a class="wiki_link_ext" href="http://archive.org/download/ElementalsFor2PianosIn19EqualTemperament/01.Undines.mp3" rel="nofollow">Undines</a>, <a class="wiki_link_ext" href="http://archive.org/download/ElementalsFor2PianosIn19EqualTemperament/02.Sylphs.mp3" rel="nofollow">Sylphs</a>, <a class="wiki_link_ext" href="http://archive.org/download/ElementalsFor2PianosIn19EqualTemperament/03.Gnomes.mp3" rel="nofollow">Gnomes</a>, and <a class="wiki_link_ext" href="http://archive.org/download/ElementalsFor2PianosIn19EqualTemperament/04.Salamanders.mp3" rel="nofollow">Salamanders</a> by Jon Lyle Smith<br />
| Augmented
<a class="wiki_link_ext" href="http://archive.org/details/AnotherAireForLute" rel="nofollow">Another Aire For Lute</a> by Jon Lyle Smith<br />
| ru
A number of compositions that were perfomed at the <a class="wiki_link_ext" href="http://midwestmicrofest.org/concerts.html" rel="nofollow">midwestmicrofest concert in 2007</a><br />
| {{nowrap|(''a'', ''b'', 0, −1)}}
Fanfare in 19-note Equal Tuning by Easley Blackwood<br />
Key signatures are the same, but with the extra notes and different enharmonic equivalents, some key signatures can get messy. For example, the key of B𝄫 would have double-flats on B and E, and flats on C, D, F, G, and A. Thinking of rewriting this key as A♯ might seem better, but then the key signature would contain double-sharps on C, F, and G, and sharps on A, B, D, and E, which is actually worse.
<a class="wiki_link_ext" href="http://chrisvaisvil.com/?p=865" rel="nofollow" target="_blank">Forgetting Even Her Beauty blog</a> <span class="ymp-btn-page-play ymp-media-7cdb4644c05849d85c1a04ed2a07a5a7"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><a class="wiki_link_ext" href="http://micro.soonlabel.com/19-ET/daily20110516-19-forgetting_even_her_beauty.mp3" rel="nofollow">play Forgetting Even Her Beauty</a></span></span></span></span> </span>by <a class="wiki_link" href="http://xenharmonic.wikispaces.com/Chris%20Vaisvil">Chris Vaisvil</a><br />
<a class="wiki_link_ext" href="http://chrisvaisvil.com/?p=855" rel="nofollow" target="_blank">19 Black Hawks for Osama blog</a> <span class="ymp-media-3badeb9b3b5a5768a5e43cea7e10b377 ymp-btn-page-play"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover ywp-page-img-link"><a class="wiki_link_ext" href="http://www.youtube.com/watch?v=gGO0R381HQs" rel="nofollow">play video for 19 Black Hawks for Osama</a> </span></span></span></span> </span>by Chris Vaisvil<br />
All 19edo chords can be named using conventional methods, expanded to include augmented and diminished seconds, thirds, sixths and sevenths. Here are the zo, gu, yo and ru triads:
<a class="wiki_link_ext" href="http://chrisvaisvil.com/?p=823" rel="nofollow" target="_blank">Summer Song blog</a> <span class="ymp-media-44691c8e07e030770b33e146e0d88212 ymp-btn-page-play"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><a class="wiki_link_ext" href="http://micro.soonlabel.com/19-ET/daily20110501-19-summer_song_mix3.mp3" rel="nofollow">play Summer Song</a></span></span></span></span> </span>by Trevor (The TwoRegs) and Norm Harris and Chris Vaisvil<br />
<a class="wiki_link_ext" href="http://chrisvaisvil.com/?p=820" rel="nofollow" target="_blank">19 ImprovFridays blog</a> <span class="ymp-btn-page-play ymp-media-c6d81d29a5290997eac85574c62b39e3"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-video ywp-link-hover ywp-page-img-link"><a class="wiki_link_ext" href="http://www.youtube.com/watch?v=-KaRXFoYwT4" rel="nofollow">play video of performance of 19 ImprovFridays</a> </span></span></span></span> </span>by Chris Vaisvil<br />
<a class="wiki_link_ext" href="http://www.youtube.com/watch?v=DSOGF4gDYu8" rel="nofollow">A Piece in 19edo</a> by Omega9<br />
! Notes of C chord
<a class="wiki_link_ext" href="http://soundcloud.com/omega9/a-piece-in-19edo-version-3" rel="nofollow">A Piece in 19edo (ver.3)</a> <em><a class="wiki_link_ext" href="http://micro.soonlabel.com/gene_ward_smith/Others/Omega9/Omega9%20-%20A%20Piece%20in%2019edo.mp3" rel="nofollow">play</a></em> by Omega9<br />
! Written name
<span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><a class="wiki_link_ext" href="http://micro.soonlabel.com/gene_ward_smith/Others/Meneghin/WTC2-24/19-edo-A-Prelude.mp3" rel="nofollow">Bach’s Prelude number 24 from Well Tempered Clavier, Book II</a></span></span></span><br />
! Spoken name
<span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><span style="right: auto;"><span class="ywp-page-play-pause ywp-page-audio ywp-link-hover ywp-page-img-link"><a class="wiki_link_ext" href="http://micro.soonlabel.com/gene_ward_smith/Others/Meneghin/WTC2-24/19-edo-B-Fugue.mp3" rel="nofollow">Bach’s Fugue number 24 from Well Tempered Clavier, Book II</a></span></span></span><br />
|-
rendered by Claudi Meneghin</body></html></pre></div>
| zo (7-over)
| 6:7:9
| 0–4–11
| C–E𝄫–G
| Cm(♭3) or Cmin(♭3) or C(d3)
| C subminor, C minor flat-three, C dim-three
|-
| gu (5-under)
| 10:12:15
| 0–5–11
| C–E♭–G
| Cm or Cmin
| C minor
|-
| yo (5-over)
| 4:5:6
| 0–6–11
| C–E–G
| C or Cmaj
| C, C major
|-
| ru (7-under)
| 14:18:21
| 0–7–11
| C–E♯–G
| C(♯3) or Cmaj(♯3) or C(A3)
| C supermajor, C major sharp-three, C aug-three
|-
| yo (5-over)
| 4:5:6:7
| 0–6–11–15
| C–E–G–B𝄫
| Ch7 or C,d7 or Cadd(d7)
| C harmonic 7, C (major) add dim-seven
|-
| gu (5-under)
| 1/(12:10:8:7)<br>(1–6/5–3/2–12/7)
| 0–5–11–15
| C–E♭–G–A♯
| Cm♯6 or CmA6 or Cm(add(♯6)) or Cm(add(A6))
| C minor (add) sharp-six, C minor (add) aug-six
|}
The last two chords illustrate how the 15\19 interval can be considered as either 7/4 or 12/7, and how 19edo conflates zo and ru ratios.
For a more complete list, see [[19edo chords #Ups and downs notation]] and [[Kite's ups and downs notation #Chords and chord progressions]].
== Notation ==
=== Standard notation ===
Standard 12edo notation can be used, whether it is staff notation (with five lines), letter [[chain-of-fifths notation]] (with standard accidentals), solfège, or sargam. Note that D# and Eb are two different notes.
Any 19edo note or interval can be [[enharmonic unison|respelled enharmonically]] by adding a double-diminished second to it or subtracting one from it. Adding a dd2 is equivalent to finding the 12edo equivalent with a higher degree, then diminishing it. For example, C# becomes Db, which is diminished to become Dbb.
* [[Ups and downs notation]] is identical to standard notation;
* Mixed [[sagittal notation]] is identical to standard notation, but pure sagittal notation exchanges sharps (♯) and flats (♭) for sagittal sharp ([[File:Sagittal sharp.png]]) and sagittal flat ([[File:Sagittal flat.png]]) respectively.
{{Sharpness-sharp1}}
=== Sagittal notation ===
This notation uses the same sagittal sequence as edos [[5edo #Sagittal notation|5]], [[12edo #Sagittal notation|12]], and [[26edo #Sagittal notation|26]], and is a subset of the notations for edos [[38edo #Sagittal notation|38]], [[57edo #Sagittal notation|57]], and [[76edo #Sagittal notation|76]].
==== Evo flavor ====
{{Sagittal chart|Evo}}
Because it includes no Sagittal symbols, this Evo Sagittal notation is identical to conventional notation.
|+ style="font-size: 105%; white-space: nowrap;" | Dodecatonic notation of 19edo
|-
! [[Degree|#]]
! [[Cent]]s
! Interval names
|-
| 0
| 0.0
| P1
|-
| 1
| 63.2
| A1, m2
|-
| 2
| 126.3
| M2, m3
|-
| 3
| 189.5
| M3
|-
| 4
| 252.6
| m4, A3
|-
| 5
| 315.8
| M4, m5
|-
| 6
| 378.9
| M5
|-
| 7
| 442.1
| A5, d6
|-
| 8
| 505.3
| P6
|-
| 9
| 568.4
| A6, m7
|-
| 10
| 631.6
| M7, d8
|-
| 11
| 694.7
| P8
|-
| 12
| 757.9
| A8, m9
|-
| 13
| 821.1
| M9, m10
|-
| 14
| 884.2
| M10
|-
| 15
| 947.4
| m11, A10
|-
| 16
| 1010.5
| M11, m12
|-
| 17
| 1073.7
| M12
|-
| 18
| 1136.8
| A12, d13
|-
| 19
| 1200.0
| P13
|}
== Approximation to JI ==
[[File:19ed2.svg|250px|thumb|right|alt=alt : Your browser has no SVG support.|Selected 19-limit intervals approximated in 19edo]]
=== Interval mappings ===
{{Q-odd-limit intervals|19}}
== Regular temperament properties ==
{| class="wikitable center-4 center-5 center-6"
|-
! rowspan="2" | [[Subgroup]]
! rowspan="2" | [[Comma list]]
! rowspan="2" | [[Mapping]]
! rowspan="2" | Optimal<br>8ve stretch (¢)
! colspan="2" | Tuning error
|-
! [[TE error|Absolute]] (¢)
! [[TE simple badness|Relative]] (%)
|-
| 2.3
| {{monzo| -30 19 }}
| {{mapping| 19 30 }}
| +2.277
| 2.277
| 3.612
|-
| 2.3.5
| 81/80, 3125/3072
| {{mapping| 19 30 44 }}
| +2.578
| 1.911
| 3.025
|-
| 2.3.5.7
| 49/48, 81/80, 126/125
| {{mapping| 19 30 44 53 }}
| +3.848
| 2.755
| 4.362
|-
| 2.3.5.7.13
| 49/48, 65/64, 81/80, 91/90
| {{mapping| 19 30 44 53 70 }}
| +4.135
| 2.530
| 4.006
|-
| 2.3.5.7.13.23
| 49/48, 65/64, 70/69, 81/80, 91/90
| {{mapping| 19 30 44 53 70 86 }}
| +3.319
| 2.936
| 4.649
|}
* 19et is lower in relative error than any previous equal temperaments in the 5-, 7-, 13-, 17-, and 19-limit—''both'' 19 and 19e val achieve this in the case of 13-limit, 19eg val in the 17-limit, and 19egh val in the 19-limit. The next equal temperaments doing better in those subgroups are [[34edo|34]], [[31edo|31]], [[27edo|27e]], [[22edo|22]], and [[26edo|26]], respectively.
* 19et is best in the 2.3.5.7.13 subgroup, and the next equal temperament that does better in this is [[53edo|53]].
=== Uniform maps ===
{{Uniform map|edo=19}}
=== Commas ===
19et [[tempering out|tempers out]] the following [[comma]]s. (Note: This assumes the [[val]] {{val| 19 30 44 53 66 70 }}.)
* [[List of 19et rank two temperaments by badness]]
* [[List of 19et rank two temperaments by complexity]]
* [[List of edo-distinct 19et rank two temperaments]]
* [[Syntonic–kleismic equivalence continuum]]
Since 19 is prime, all rank-2 temperaments in 19edo have one period per octave (i.e. are linear). Therefore you can make a correspondence between intervals and the linear temperaments they generate.
19edo is a promising option as a meantone tuning for pianos if split sharps are acceptable, since pianos are frequently tuned with stretched octaves due to the slight [[inharmonicity]] inherent in their strings. It also works well with harpsichords, since many have been, and are, built with split sharps.
Octave stretching also means that an out-of-tune interval can be replaced with a compounded or inverted version of it which is near-[[just]]. For example, if we are using [[49ed6]] or [[30edt]] (which tune 6:1 and 3:1 just and have octaves stretched by 2.8 and 4.57{{c}}, respectively), then we have near-just minor thirds (6:5), compound major thirds (as 5:1), and compound fifths (as 6:1), giving us versions of everything in the 5-odd-limit [[tonality diamond]]. The compound major and minor triads (1:5:6 and 30:6:5) are near-just as well. Another possible choice is [[ZPI|65zpi]].
[[File:Vaisvil-19edo-guitar-IMG00145-1024x768.jpg|512x384px|thumb|none|19 note per octave Ibanez conversion by Brad Smith (Indianapolis)]]
[[File:Bass19.jpg|alt=19edo 5 string Bass 34"-37" scale length|512x384px|thumb|none|19edo bass conversion by Ron Sword]]
== Music ==
{{Main| 19edo/Music }}
{{Catrel| 19edo tracks }}
; [http://micro.soonlabel.com/19-ET/ XA 19-ET Index]
; A number of compositions that were perfomed at the [http://midwestmicrofest.org/concerts.html midwestmicrofest concert in 2007]{{dead link}}
== See also ==
* [[19edo modes]]
* [[19edo chords]]
* [[Strictly proper 19edo scales]]
* [[How to tune a 19edo guitar by ear]]
* [[Primer for 19edo]]
* [[Mason Green's New Common Practice Notation]]
* [[Extraclassical tonality]]
* [[Lumatone mapping for 19edo]]
== Further reading ==
* [[Darreg, Ivor]]. ''[http://www.tonalsoft.com/sonic-arts/darreg/case.htm A Case for Nineteen]''. 1982.
* Darreg, Ivor. ''[http://www.microstick.net/nineteenarticle.htm Nineteen for the Nineties]''{{dead link}}. (Unknown date of publication).
* Howe, Hubert S., Jr. [http://qcpages.qc.edu/%7Ehowe/articles/19-Tone%20Theory.html 19-Tone Theory and Applications]. c. 2004.
* [[Sethares, William A]]. [http://sethares.engr.wisc.edu/tet19/guitarchords19.html Tunings for 19 Tone Equal Tempered Guitar]. 1991.
* [[Sword, Ron]]. ''[http://www.metatonalmusic.com/books.html Enneadecaphonic Scales for Guitar: A Repository of Scales, Chord-Scales, Notations and Techniques for Nineteen Equal Divisions of the Octave]''. 2010.
* Yasser, Joseph. ''[https://www.worldcat.org/fr/title/726192994 Theory of Evolving Tonality]''. 1932.
== External links ==
* [http://tonalsoft.com/enc/number/19edo.aspx 19-tone equal-temperament and 1/3-comma meantone / 19-edo / 19-ed2] on the [[Tonalsoft Encyclopedia]]
* [http://www.n-ism.org/Projects/microtonalism.php Microtonalism] by Ingrid Pearson, Graham Hair, Dougie McGilvray, Nick Bailey, Amanda Morrison and Richard Parncutt (from n-ISM, the Network for Interdisciplinary Studies in Science, Technology, and Music)
* [http://mtg.redkeylabs.com/index.php?topic=6.0 Forum Discussion with some 19-EDO xenharmonic scales Hanson (Keemun), Liese, Negri, Magic, Semaphore, Sensi played on guitar].
19 equal divisions of the octave (abbreviated 19edo or 19ed2), also called 19-tone equal temperament (19tet) or 19 equal temperament (19et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 19 equal parts of about 63.2 ¢ each. Each step represents a frequency ratio of 21/19, or the 19th root of 2.
Interest in this tuning system goes back to the sixteenth century, when composer Guillaume Costeley used it in his chanson Seigneur Dieu ta pitié of 1558. Costeley understood and desired the circulating aspect of this tuning, which he defined as dividing the just major second into three approximately equal parts. Costeley had other compositions that made use of intervals, such as the diminished third, which have a meaningful context in 19edo, but not in other tuning systems contemporary with the work.
In 1577, music theorist Francisco de Salinas proposed 1/3-comma meantone, in which the fifth is 694.786 ¢; the fifth of 19edo is 694.737 ¢, which is only a twentieth of a cent flatter. Salinas suggested tuning nineteen tones to the octave to this tuning, which comes within less than one cent of closing exactly, so that his suggestion is effectively 19edo.
In 1835, mathematician and music theorist Wesley Woolhouse proposed it as a more practical alternative to meantone tunings he regarded as better, such as 50 equal temperament (summary of Woolhouse's essay).
Theory
19edo is the second edo, after 12edo, which is able to approximate 5-limit intervals and chords with tolerable accuracy (unless you count 15edo, which has a 18-cent-sharp fifth). Having an almost just minor third and perfect fifths and major thirds about 7 cents flat, it serves as a good tuning for meantone. Unlike 12edo, where enharmonic notes are conflated, 19edo distinguishes them, and differs from 17edo in that its diatonic semitone is wider than the chromatic semitone, rather than narrower. In fact, it is nearly identical to the enharmonic scale of 1/3-comma meantone, and can be considered a closed form thereof.
It is less successful in the 7-limit as it conflates the septimal subminor third (7/6) with the septimal whole tone (8/7), but it is still better than 12edo overall.
Besides meantone, 19edo is also suitable for magic/muggles temperament, because five of its major thirds are equivalent to one of its twelfths. Its 7-step supermajor third can be used for sensi, whose generator is a very sharp major third, two of which make an approximate 5/3 major sixth.
For all of these there are more optimal tunings: the fifth of 19edo is flatter than the usual for meantone, and 31edo is more optimal. Similarly, the generating interval of magic temperament is a major third, and again 19edo's is flatter; 41edo more closely matches it. It does make for a good tuning for muggles, but in 19edo it is the same as magic. Finally, 19edo can be used as a tuning for sensi, though 46edo provides a better sensi tuning.
However, for all of these 19edo has the practical advantage of requiring fewer pitches, which makes it easier to implement in physical instruments, and many 19edo instruments have been built. 19edo also has the advantage of being excellent for negri, keemun, godzilla, muggles, and triton/liese. Keemun and negri are of particular note for being very simple 7-limit temperaments, with their mos scales in 19edo offering a great abundance of septimal tetrads. The Graham complexity of the 7-odd-limit tetrad is 6 for keemun, 7 for negri, 8 for godzilla, 10 for meantone, 11 for triton, 12 for magic/muggles, and 13 for sensi.
As a means of extending harmony
Because 19edo's 5-limit chords are more blended and concordant than those of 12edo, it can be a much better candidate for using alternate forms of harmony such as quartal, secundal, and poly chords. William Lynch suggests the use of seventh chords of various types to be the fundamental sonorities with a triad deemed as incomplete. Higher extensions involving the 7th harmonic as well as other non-diatonic chord extensions which tend to clash in 12edo blend much better in 19edo.
In addition, Joseph Yasser talks about the idea of a 12-tone supra-diatonic scale where the 7-tone major scale in 19edo becomes akin to the pentatonic of western music; as it would sound to a future generation, ambiguous and not tonally fortified. As paraphrased "A system in which the undeniable laws of tonal gravity exist, yet in a much more complex tonal universe." Yasser believed that music would eventually move to a 19-tone system with a 12-note supra-diatonic scale would become the standard. While this has yet to happen, Yasser's concept of supra-diatonicity is intriguing and worth exploring for those wanting to extend tonality without sounding too alien.
19edo also closely approximates most of the intervals of Bozuji tuning, a 21st century tuning based on Gioseffo Zarlino's approach to just intonation. with most of the adjacent diatonic diminished and augmented intervals of Bozuji tuning represented enharmonically by one interval in 19edo.
Due to the narrow whole tones and wide diatonic semitones, 19edo's diatonic scale tends to sound somewhat dull compared to 12edo, but the pentatonic scale is said by many to sound much more expressive owing to the significantly larger contrast between the narrow whole tone and wide minor third. While 12edo has an expressive diatonic and dull pentatonic, the reverse is true in 19. Pentatonicism thus becomes more important in 19edo, and one option is to use the pentatonic scale as a sort of "super-chord", with "chord progressions" being modulations between pentatonic subsets of the superdiatonic scale.
Adaptive tuning
The no-11's 13-limit is represented relatively well and consistently. 19edo's negri, sensi and godzilla scales have many 13-limit chords. (You can think of the Sensi[8] 3L 5s mos scale as 19edo's answer to the diminished scale. Both are made of two diminished seventh chords, but Sensi[8] gives you additional ratios of 7 and 13.) Its diminished fifth is also a very accurate approximation of the 23rd harmonic, being only 3.3 ¢ off 23/16.
Practically 19edo can be used adaptively on instruments which allow you to bend notes up: by different amounts, the 3rd, 5th, 7th, and 13th harmonics are all tuned flat. This is in contrast to 12edo, where this is not possible since the 5th and 7th harmonics are not only much farther from just than they are in 19edo, but fairly sharp already.
Another option would be to use octave stretching, which has similar benefits to adaptive use, but it also works for fixed-pitch Instruments. For more on that see the section on octave stretch.
Subsets and supersets
19edo is the 8th prime edo, following 17edo and preceding 23edo. As such, it does not contain any nontrivial subset edos, though it contains 19ed4.
38edo, which doubles 19edo, provides an approximation of harmonic 11 that works well with the flat tendency of its 5-limit mapping. See undevigintone. 57edo effectively corrects the harmonic 7 to just, although it is 76edo that fits the best. See meanmag.
Miscellaneous properties
19edo has the flattest possible fifth of any edo that can possibly be diamond monotone in the 15-odd-limit. Using 11\19 as the fifth, the sharpest possible mapping of 5/4 where 10/9 is no greater than 9/8 is 6\19, so the sharpest possible 15/8 is 17\19. Here 16/15 is a quarter of 4/3 (as in any negri tuning), so 15/14, 14/13, and 13/12 must all be equated with 16/15 to 2\19 for them to be monotone in size. If the fifth were any flatter, 5/4 and 15/8 would have to be flatter, and 16/15 would have to be sharper, so diamond monotone in the 15-odd-limit becomes impossible. 19edo is, in fact, diamond monotone in the 15-odd-limit, and even the 17-odd-limit (see Monotonicity limits of small EDOs). The sharpest fifth where 15-odd-limit is possible is 22\37.
Key signatures are the same, but with the extra notes and different enharmonic equivalents, some key signatures can get messy. For example, the key of B𝄫 would have double-flats on B and E, and flats on C, D, F, G, and A. Thinking of rewriting this key as A♯ might seem better, but then the key signature would contain double-sharps on C, F, and G, and sharps on A, B, D, and E, which is actually worse.
All 19edo chords can be named using conventional methods, expanded to include augmented and diminished seconds, thirds, sixths and sevenths. Here are the zo, gu, yo and ru triads:
Color of the third
JI chord
Edosteps
Notes of C chord
Written name
Spoken name
zo (7-over)
6:7:9
0–4–11
C–E𝄫–G
Cm(♭3) or Cmin(♭3) or C(d3)
C subminor, C minor flat-three, C dim-three
gu (5-under)
10:12:15
0–5–11
C–E♭–G
Cm or Cmin
C minor
yo (5-over)
4:5:6
0–6–11
C–E–G
C or Cmaj
C, C major
ru (7-under)
14:18:21
0–7–11
C–E♯–G
C(♯3) or Cmaj(♯3) or C(A3)
C supermajor, C major sharp-three, C aug-three
yo (5-over)
4:5:6:7
0–6–11–15
C–E–G–B𝄫
Ch7 or C,d7 or Cadd(d7)
C harmonic 7, C (major) add dim-seven
gu (5-under)
1/(12:10:8:7) (1–6/5–3/2–12/7)
0–5–11–15
C–E♭–G–A♯
Cm♯6 or CmA6 or Cm(add(♯6)) or Cm(add(A6))
C minor (add) sharp-six, C minor (add) aug-six
The last two chords illustrate how the 15\19 interval can be considered as either 7/4 or 12/7, and how 19edo conflates zo and ru ratios.
Standard 12edo notation can be used, whether it is staff notation (with five lines), letter chain-of-fifths notation (with standard accidentals), solfège, or sargam. Note that D# and Eb are two different notes.
Any 19edo note or interval can be respelled enharmonically by adding a double-diminished second to it or subtracting one from it. Adding a dd2 is equivalent to finding the 12edo equivalent with a higher degree, then diminishing it. For example, C# becomes Db, which is diminished to become Dbb.
Mixed sagittal notation is identical to standard notation, but pure sagittal notation exchanges sharps (♯) and flats (♭) for sagittal sharp () and sagittal flat () respectively.
Step offset
−2
−1
0
+1
+2
Symbol
Sagittal notation
This notation uses the same sagittal sequence as edos 5, 12, and 26, and is a subset of the notations for edos 38, 57, and 76.
Evo flavor
Because it includes no Sagittal symbols, this Evo Sagittal notation is identical to conventional notation.
19et is lower in relative error than any previous equal temperaments in the 5-, 7-, 13-, 17-, and 19-limit—both 19 and 19e val achieve this in the case of 13-limit, 19eg val in the 17-limit, and 19egh val in the 19-limit. The next equal temperaments doing better in those subgroups are 34, 31, 27e, 22, and 26, respectively.
19et is best in the 2.3.5.7.13 subgroup, and the next equal temperament that does better in this is 53.
Since 19 is prime, all rank-2 temperaments in 19edo have one period per octave (i.e. are linear). Therefore you can make a correspondence between intervals and the linear temperaments they generate.
19edo is a promising option as a meantone tuning for pianos if split sharps are acceptable, since pianos are frequently tuned with stretched octaves due to the slight inharmonicity inherent in their strings. It also works well with harpsichords, since many have been, and are, built with split sharps.
Octave stretching also means that an out-of-tune interval can be replaced with a compounded or inverted version of it which is near-just. For example, if we are using 49ed6 or 30edt (which tune 6:1 and 3:1 just and have octaves stretched by 2.8 and 4.57 ¢, respectively), then we have near-just minor thirds (6:5), compound major thirds (as 5:1), and compound fifths (as 6:1), giving us versions of everything in the 5-odd-limit tonality diamond. The compound major and minor triads (1:5:6 and 30:6:5) are near-just as well. Another possible choice is 65zpi.
Microtonalism by Ingrid Pearson, Graham Hair, Dougie McGilvray, Nick Bailey, Amanda Morrison and Richard Parncutt (from n-ISM, the Network for Interdisciplinary Studies in Science, Technology, and Music)