### Re: 13-limit JI

Posted:

**Sat Oct 22, 2016 11:35 pm**On 2016-Sep-13, I wrote to Daniel Spreadbury (at Steinberg):

Hi Daniel,

I did post your explanation to the Sagittal forum. You can see a response here:

http://forum.sagittal.org/viewtopic.php?p=372#p372

I just want to point out that since Dorico will only allow microtonality via EDOs, in order to not be seen as discriminating against Just Intonation, Dorico will need to support at least 224-EDO as it is the smallest adequate approximation. Will it support notation and playback of 224-EDO?

When you say that EDOs, and the delta for each accidental (or composite), will be defined as rational values (i.e. fractions), what will they be fractions of? I'm guessing fractions of an octave (i.e. multiply them by 1200 and you'll have cents), rather than frequency ratios (e.g. where a syntonic comma alteration would be described as 81/80). Is that correct?

-- Dave

Hi Daniel,

I did post your explanation to the Sagittal forum. You can see a response here:

http://forum.sagittal.org/viewtopic.php?p=372#p372

I just want to point out that since Dorico will only allow microtonality via EDOs, in order to not be seen as discriminating against Just Intonation, Dorico will need to support at least 224-EDO as it is the smallest adequate approximation. Will it support notation and playback of 224-EDO?

When you say that EDOs, and the delta for each accidental (or composite), will be defined as rational values (i.e. fractions), what will they be fractions of? I'm guessing fractions of an octave (i.e. multiply them by 1200 and you'll have cents), rather than frequency ratios (e.g. where a syntonic comma alteration would be described as 81/80). Is that correct?

-- Dave

Daniel Spreadbury wrote:Hi Dave,

Playback of microtonality will not be implemented in the first release, but I believe the necessary features to notate music in any EDO-based system should be there. The delta for accidentals is defined as fractions of an octave, but the denominator can be anything you like, so a flat would be -1/12 in its simplest form, and a maqam accidental would be -1/53 in its simplest form, and so on.

Daniel