Topic: 37 EDO

1 scales

File Description Notes Period (¢)
37-EDO_generator11_8 11 1200.0

Thread (5 messages)

From: Jake Freivald (2012-08-22)
Subject: 37 EDO

37 EDO is funny.

Prime 11 is perfect (less than 0.1 cent off), while primes 5, 7, and 13 are
excellent (just a few cents error). Prime 3 isn't great (12 cents off), but
it's usable enough. (I don't mind the sharp 3/2, but I don't like the
counterpart flat 4/3.) All of the following intervals can be found in 37
EDO with less than 9 cents error:

     14/13
     11/10
      7/6
     13/11
      6/5
     11/9
      5/4
     14/11
     13/10
     11/8
      7/5
     10/7
     16/11
      8/5
      7/4

13/10 has less than a cent error. 10/7 and 7/5 have less than two cents. If
you like 2.3.5.7.11.13, this seems like an EDO you can get behind.

Good stuff, right? Problem is, I can't get a decent mapping out of it. The
13-limit patent val is
< 37 59 86 104 128 137 |
and that works fine for 13/11 (<3 cents sharp) and 14/11 (<5 cents sharp),
but the 11/9 gets mapped to 324 cents (23 cents flat). There's a better
11/9 in the pitch set, though: 357 cents, or 10 cents sharp. The natural
thing to do is bring the mapping for 3/1 down to 58 steps, but when I do,
11/9 gets mapped to 389 cents -- which is really that nearly-perfect 5/4. I
could use 60/49 and 49/40 (both about 351 cents) instead of 11/9, but that
seems to add complexity and eliminate the eleven-ness of the darn thing.

So don't ask me what that 357-cent neutral third is, but it's not an 11/9.
:)

Because 13/11 * 14/11 = 3/2, 37 EDO tempers out 364/363. According to my
spreadsheet, 37 EDO (using the patent val) also tempers out 2401/2400 (the
breedsma, so the 49/40 and 60/49 neutral thirds are equated -- if you want
to map the 357-cent neutral third to those intervals instead of 11/9).
Those seem useful. Here are other commas that get tempered out (limiting
myself to the 13 prime limit):

5-limit
|  17  1  -8 >  11.45  393216/390625  Würschmidt's  comma
| -16 -6  11 >  37.72                 Sycamore  comma
|  1  -5   3 >  49.17     250/243     Maximal  diesis

7-limit
| -5  -1 -2  4 >   0.72  2401/2400  Breedsma
| 11   1 -3 -2 >   5.36  6144/6125  porwell  comma
|  6   0 -5  2 >   6.08  3136/3125  middle  second  comma
|  0  -2  5 -3 >  21.18  3125/3087  major  BP  diesis
| -5  -3  3  1 >  21.90   875/864   keema
|  6  -2  0 -1 >  27.26    64/63    septimal  comma,  Archytas'  comma
|  1  -3 -2  3 >  27.99   686/675   senga

11-limit
|   5  -1  3  0 -3 >   3.03   4000/3993   undecimal  schisma,  Wizardharry
|  -7  -1  1  1  1 >   4.50    385/384    undecimal  kleisma,  Keenanisma
|  16   0  0 -2 -3 >   8.39  65536/65219  orgonisma
|   4   0 -2 -1  1 >   9.86    176/175    valinorsma
|  -3  -1 -1  0  2 >  14.37    121/120    undecimal  seconds  comma
|   2  -2  2  0 -1 >  17.40    100/99     Ptolemy's  comma

13-limit
|  3  0  2  0  1 -3 >  2.36  2200/2197   2.36  Parizek  comma,  petrma
|  2 -1  0  1 -2  1 >  4.76   364/363    4.76  gentle  comma
|  2 -1 -1  2  0 -1 >  8.86   196/195    8.86  mynucuma
| -1 -2 -1  1  0  1 >  19.13   91/90    19.13  superleap

I don't really know what a lot of those mean, but they're there if you want
them.

To see if I could exploit some of the nearly-just intervals in 37 EDO, I've
done something like a billion attempts at using generators to create MOS
scales. Unfortunately, few of them have reasonable size (say, 13 or fewer
tones) and still take advantage of all -- or even many! -- of the great
tones in the scale, and most of them are very improper.

At any rate, thinking I should try to do *something* to try out 37, I
settled on an 11-note MOS that uses 11/8 as a generator. Here it is:

! C:\Program Files (x86)\Scala22\37-EDO_generator11_8.scl
!

 11
!
 162.16215
 259.45945
 356.75675
 454.05405
 551.35135
 713.51350
 810.81080
 908.10810
 1005.40540
 1102.70270
 2/1

It's strictly proper, and almost every mode of this scale has an 11/8,
naturally, since that's the generator. Only this mode has a 3/2. There's a
mix of 11/9-ish neutral thirds, 5/4 major thirds, and 13/11 minor thirds in
the other modes. There are no 14/11 major thirds. Interestingly, many modes
have a 745-cent interval seems to go pretty well with the 551-cent interval
-- I suppose it's like putting a 10/9 or 9/8 over the 11/8. The scale
surprised me in a few ways that I haven't been able to properly exploit and
play around with.

Here's a very brief ditty I did using this scale. It happened to work out
to be about 37 seconds long, which seemed appropriate for 37 EDO, so I made
it fit. I didn't exploit the other modes, so the melody mostly uses the
sharp neutral third, sharp fifth, 11/8, and 8/5.

http://soundcloud.com/jdfreivald/37-seconds

Regards,
Jake
From: cityoftheasleep (2012-08-25)
Subject: Re: 37 EDO

Why not map it as 2.5.7.9.11.13?  It kinda makes more sense that way if you think of it as a subset of 74-ED2, where you'd use the meantone mapping and put 3 on an interval that's halfway between the two 3's of 37-ED2 (just a bit sharp of 697 cents).  Or you could do it Mike Battaglia style and map it as 2.3.5.7.9'.11.13, where the 9' isn't 3^2 but its own "prime".  

-Igs

--- In tuning@yahoogroups.com, Jake Freivald <jdfreivald@...> wrote:
>
> 37 EDO is funny.
> 
> Prime 11 is perfect (less than 0.1 cent off), while primes 5, 7, and 13 are
> excellent (just a few cents error). Prime 3 isn't great (12 cents off), but
> it's usable enough. (I don't mind the sharp 3/2, but I don't like the
> counterpart flat 4/3.) All of the following intervals can be found in 37
> EDO with less than 9 cents error:
> 
>      14/13
>      11/10
>       7/6
>      13/11
>       6/5
>      11/9
>       5/4
>      14/11
>      13/10
>      11/8
>       7/5
>      10/7
>      16/11
>       8/5
>       7/4
> 
> 13/10 has less than a cent error. 10/7 and 7/5 have less than two cents. If
> you like 2.3.5.7.11.13, this seems like an EDO you can get behind.
> 
> Good stuff, right? Problem is, I can't get a decent mapping out of it. The
> 13-limit patent val is
> < 37 59 86 104 128 137 |
> and that works fine for 13/11 (<3 cents sharp) and 14/11 (<5 cents sharp),
> but the 11/9 gets mapped to 324 cents (23 cents flat). There's a better
> 11/9 in the pitch set, though: 357 cents, or 10 cents sharp. The natural
> thing to do is bring the mapping for 3/1 down to 58 steps, but when I do,
> 11/9 gets mapped to 389 cents -- which is really that nearly-perfect 5/4. I
> could use 60/49 and 49/40 (both about 351 cents) instead of 11/9, but that
> seems to add complexity and eliminate the eleven-ness of the darn thing.
> 
> So don't ask me what that 357-cent neutral third is, but it's not an 11/9.
> :)
> 
> Because 13/11 * 14/11 = 3/2, 37 EDO tempers out 364/363. According to my
> spreadsheet, 37 EDO (using the patent val) also tempers out 2401/2400 (the
> breedsma, so the 49/40 and 60/49 neutral thirds are equated -- if you want
> to map the 357-cent neutral third to those intervals instead of 11/9).
> Those seem useful. Here are other commas that get tempered out (limiting
> myself to the 13 prime limit):
> 
> 5-limit
> |  17  1  -8 >  11.45  393216/390625  Würschmidt's  comma
> | -16 -6  11 >  37.72                 Sycamore  comma
> |  1  -5   3 >  49.17     250/243     Maximal  diesis
> 
> 7-limit
> | -5  -1 -2  4 >   0.72  2401/2400  Breedsma
> | 11   1 -3 -2 >   5.36  6144/6125  porwell  comma
> |  6   0 -5  2 >   6.08  3136/3125  middle  second  comma
> |  0  -2  5 -3 >  21.18  3125/3087  major  BP  diesis
> | -5  -3  3  1 >  21.90   875/864   keema
> |  6  -2  0 -1 >  27.26    64/63    septimal  comma,  Archytas'  comma
> |  1  -3 -2  3 >  27.99   686/675   senga
> 
> 11-limit
> |   5  -1  3  0 -3 >   3.03   4000/3993   undecimal  schisma,  Wizardharry
> |  -7  -1  1  1  1 >   4.50    385/384    undecimal  kleisma,  Keenanisma
> |  16   0  0 -2 -3 >   8.39  65536/65219  orgonisma
> |   4   0 -2 -1  1 >   9.86    176/175    valinorsma
> |  -3  -1 -1  0  2 >  14.37    121/120    undecimal  seconds  comma
> |   2  -2  2  0 -1 >  17.40    100/99     Ptolemy's  comma
> 
> 13-limit
> |  3  0  2  0  1 -3 >  2.36  2200/2197   2.36  Parizek  comma,  petrma
> |  2 -1  0  1 -2  1 >  4.76   364/363    4.76  gentle  comma
> |  2 -1 -1  2  0 -1 >  8.86   196/195    8.86  mynucuma
> | -1 -2 -1  1  0  1 >  19.13   91/90    19.13  superleap
> 
> I don't really know what a lot of those mean, but they're there if you want
> them.
> 
> To see if I could exploit some of the nearly-just intervals in 37 EDO, I've
> done something like a billion attempts at using generators to create MOS
> scales. Unfortunately, few of them have reasonable size (say, 13 or fewer
> tones) and still take advantage of all -- or even many! -- of the great
> tones in the scale, and most of them are very improper.
> 
> At any rate, thinking I should try to do *something* to try out 37, I
> settled on an 11-note MOS that uses 11/8 as a generator. Here it is:
> 
> ! C:\Program Files (x86)\Scala22\37-EDO_generator11_8.scl
> !
> 
>  11
> !
>  162.16215
>  259.45945
>  356.75675
>  454.05405
>  551.35135
>  713.51350
>  810.81080
>  908.10810
>  1005.40540
>  1102.70270
>  2/1
> 
> It's strictly proper, and almost every mode of this scale has an 11/8,
> naturally, since that's the generator. Only this mode has a 3/2. There's a
> mix of 11/9-ish neutral thirds, 5/4 major thirds, and 13/11 minor thirds in
> the other modes. There are no 14/11 major thirds. Interestingly, many modes
> have a 745-cent interval seems to go pretty well with the 551-cent interval
> -- I suppose it's like putting a 10/9 or 9/8 over the 11/8. The scale
> surprised me in a few ways that I haven't been able to properly exploit and
> play around with.
> 
> Here's a very brief ditty I did using this scale. It happened to work out
> to be about 37 seconds long, which seemed appropriate for 37 EDO, so I made
> it fit. I didn't exploit the other modes, so the melody mostly uses the
> sharp neutral third, sharp fifth, 11/8, and 8/5.
> 
> http://soundcloud.com/jdfreivald/37-seconds
> 
> Regards,
> Jake
>
From: monz (2012-08-26)
Subject: Re: 37 EDO

Hi Jake and Igs,

I posted here about 37-edo not too long ago.
Have you seen my Encyclopedia page about it?

http://tonalsoft.com/enc/number/37-edo/37edo.aspx

... i should mention that for some reason the graph that is
supposed to end the section "Some 41-limit JI ratios
mapped to 37-edo" is not appearing ... i don't know why --
the image file is uploaded to my website and the html code
on the page seems to be correct.

-monz

--- In tuning@yahoogroups.com, "cityoftheasleep" <igliashon@...> wrote:
>
> Why not map it as 2.5.7.9.11.13?  It kinda makes more sense that way if you think of it as a subset of 74-ED2, where you'd use the meantone mapping and put 3 on an interval that's halfway between the two 3's of 37-ED2 (just a bit sharp of 697 cents).  Or you could do it Mike Battaglia style and map it as 2.3.5.7.9'.11.13, where the 9' isn't 3^2 but its own "prime".  
> 
> -Igs
> 
> --- In tuning@yahoogroups.com, Jake Freivald <jdfreivald@> wrote:
> >
> > 37 EDO is funny.
> > 
> > Prime 11 is perfect (less than 0.1 cent off), while primes 5, 7, and 13 are
> > excellent (just a few cents error). Prime 3 isn't great (12 cents off), but
> > it's usable enough. (I don't mind the sharp 3/2, but I don't like the
> > counterpart flat 4/3.) All of the following intervals can be found in 37
> > EDO with less than 9 cents error:
> > 
> >      14/13
> >      11/10
> >       7/6
> >      13/11
> >       6/5
> >      11/9
> >       5/4
> >      14/11
> >      13/10
> >      11/8
> >       7/5
> >      10/7
> >      16/11
> >       8/5
> >       7/4
> > 
> > 13/10 has less than a cent error. 10/7 and 7/5 have less than two cents. If
> > you like 2.3.5.7.11.13, this seems like an EDO you can get behind.
> > 
> > Good stuff, right? Problem is, I can't get a decent mapping out of it. The
> > 13-limit patent val is
> > < 37 59 86 104 128 137 |
> > and that works fine for 13/11 (<3 cents sharp) and 14/11 (<5 cents sharp),
> > but the 11/9 gets mapped to 324 cents (23 cents flat). There's a better
> > 11/9 in the pitch set, though: 357 cents, or 10 cents sharp. The natural
> > thing to do is bring the mapping for 3/1 down to 58 steps, but when I do,
> > 11/9 gets mapped to 389 cents -- which is really that nearly-perfect 5/4. I
> > could use 60/49 and 49/40 (both about 351 cents) instead of 11/9, but that
> > seems to add complexity and eliminate the eleven-ness of the darn thing.
> > 
> > So don't ask me what that 357-cent neutral third is, but it's not an 11/9.
> > :)
> > 
> > Because 13/11 * 14/11 = 3/2, 37 EDO tempers out 364/363. According to my
> > spreadsheet, 37 EDO (using the patent val) also tempers out 2401/2400 (the
> > breedsma, so the 49/40 and 60/49 neutral thirds are equated -- if you want
> > to map the 357-cent neutral third to those intervals instead of 11/9).
> > Those seem useful. Here are other commas that get tempered out (limiting
> > myself to the 13 prime limit):
> > 
> > 5-limit
> > |  17  1  -8 >  11.45  393216/390625  Würschmidt's  comma
> > | -16 -6  11 >  37.72                 Sycamore  comma
> > |  1  -5   3 >  49.17     250/243     Maximal  diesis
> > 
> > 7-limit
> > | -5  -1 -2  4 >   0.72  2401/2400  Breedsma
> > | 11   1 -3 -2 >   5.36  6144/6125  porwell  comma
> > |  6   0 -5  2 >   6.08  3136/3125  middle  second  comma
> > |  0  -2  5 -3 >  21.18  3125/3087  major  BP  diesis
> > | -5  -3  3  1 >  21.90   875/864   keema
> > |  6  -2  0 -1 >  27.26    64/63    septimal  comma,  Archytas'  comma
> > |  1  -3 -2  3 >  27.99   686/675   senga
> > 
> > 11-limit
> > |   5  -1  3  0 -3 >   3.03   4000/3993   undecimal  schisma,  Wizardharry
> > |  -7  -1  1  1  1 >   4.50    385/384    undecimal  kleisma,  Keenanisma
> > |  16   0  0 -2 -3 >   8.39  65536/65219  orgonisma
> > |   4   0 -2 -1  1 >   9.86    176/175    valinorsma
> > |  -3  -1 -1  0  2 >  14.37    121/120    undecimal  seconds  comma
> > |   2  -2  2  0 -1 >  17.40    100/99     Ptolemy's  comma
> > 
> > 13-limit
> > |  3  0  2  0  1 -3 >  2.36  2200/2197   2.36  Parizek  comma,  petrma
> > |  2 -1  0  1 -2  1 >  4.76   364/363    4.76  gentle  comma
> > |  2 -1 -1  2  0 -1 >  8.86   196/195    8.86  mynucuma
> > | -1 -2 -1  1  0  1 >  19.13   91/90    19.13  superleap
> > 
> > I don't really know what a lot of those mean, but they're there if you want
> > them.
> > 
> > To see if I could exploit some of the nearly-just intervals in 37 EDO, I've
> > done something like a billion attempts at using generators to create MOS
> > scales. Unfortunately, few of them have reasonable size (say, 13 or fewer
> > tones) and still take advantage of all -- or even many! -- of the great
> > tones in the scale, and most of them are very improper.
> > 
> > At any rate, thinking I should try to do *something* to try out 37, I
> > settled on an 11-note MOS that uses 11/8 as a generator. Here it is:
> > 
> > ! C:\Program Files (x86)\Scala22\37-EDO_generator11_8.scl
> > !
> > 
> >  11
> > !
> >  162.16215
> >  259.45945
> >  356.75675
> >  454.05405
> >  551.35135
> >  713.51350
> >  810.81080
> >  908.10810
> >  1005.40540
> >  1102.70270
> >  2/1
> > 
> > It's strictly proper, and almost every mode of this scale has an 11/8,
> > naturally, since that's the generator. Only this mode has a 3/2. There's a
> > mix of 11/9-ish neutral thirds, 5/4 major thirds, and 13/11 minor thirds in
> > the other modes. There are no 14/11 major thirds. Interestingly, many modes
> > have a 745-cent interval seems to go pretty well with the 551-cent interval
> > -- I suppose it's like putting a 10/9 or 9/8 over the 11/8. The scale
> > surprised me in a few ways that I haven't been able to properly exploit and
> > play around with.
> > 
> > Here's a very brief ditty I did using this scale. It happened to work out
> > to be about 37 seconds long, which seemed appropriate for 37 EDO, so I made
> > it fit. I didn't exploit the other modes, so the melody mostly uses the
> > sharp neutral third, sharp fifth, 11/8, and 8/5.
> > 
> > http://soundcloud.com/jdfreivald/37-seconds
> > 
> > Regards,
> > Jake
> >
>
From: Jake Freivald (2012-08-27)
Subject: Re: [tuning] Re: 37 EDO

Igs, good to see you here -- I thought you had dropped off. Since I
don't mind the very-sharp 3/2, but I still want to use the kinda-sharp
11/9, I think it makes the most sense to do it Battaglia-style (9' is
its own prime). I remember seeing people talk about that way of
thinking, but had forgotten it. It suits the way I'm considering the
scales I've generated in it. Thanks for the thought.

Monz, I had forgotten that 37 was the object of your recent
discussion. I had just been looking through EDOs in a spreadsheet that
calculates intervals and commas and the like (yes, I'm the life of the
party). I especially like your diagrams on the encyclopedia! Excellent
view into what's going on.

One of the things I liked about dabbling in 37 is the perfect 11/8
that can have a major second (a little flat) piled on top of it -- I
haven't previously found myself liking 745 cents over the root, but
when played on top of a pure 11/8 (551 cents) it sounds pretty good.
It doesn't sound like an out-of-tune 3/2, as it sometimes does, but it
still seems stretched somehow without being discordant. Anyway, I wish
I had better capabilities to use 13+ tone scales, because I think this
EDO could be really cool for extended scales.

Thanks,
Jake
From: monz (2012-08-27)
Subject: Re: 37 EDO

Thanks to Graham Breed for helping me finally track down the
missing hyphen which was preventing that graph from loading.
All is well now.

-monz

--- In tuning@yahoogroups.com, "monz" <joemonz@...> wrote:
>
> Hi Jake and Igs,
> 
> I posted here about 37-edo not too long ago.
> Have you seen my Encyclopedia page about it?
> 
> http://tonalsoft.com/enc/number/37-edo/37edo.aspx
> 
> ... i should mention that for some reason the graph that is
> supposed to end the section "Some 41-limit JI ratios
> mapped to 37-edo" is not appearing ... i don't know why --
> the image file is uploaded to my website and the html code
> on the page seems to be correct.
> 
> -monz