Topic: 23-and-29 only, and sagittal ET notation
1 scales
| File | Description | Notes | Period (¢) | Limit |
|---|---|---|---|---|
| 11lwt | 11-limit Rational Well-temperament | 12 | 1200.0 | 11 |
Thread (7 messages)
From: Jacob (2004-07-23) Subject: 23-and-29 only, and sagittal ET notation First of all, has anyone noticed that 29/16 is one cent away from six steps of 7 equal? Ain't that something? Two implications I see: 1. 7 equal could be notated with ABCDEFG defined as a "circle" of sevenths, or seconds (32/29's), and its lower multiples with accidentals in accordance with some non-3 lattice. 2. In particular, a 21-note periodicity block in 23,29 only, defined by "unison vectors" 23^(-3)2*29^3 and 23^3 29^(-4): 0: 1/1 0.000 unison, perfect prime 1: 24389/23552 60.457 2: 560947/524288 117.006 3: 594823321/536870912 177.463 4: 841/736 230.880 5: 19343/16384 287.429 6: 20511149/16777216 347.886 7: 29/23 401.303 8: 707281/541696 461.760 9: 707281/524288 518.309 10: 374151649/268435456 574.857 11: 24389/16928 632.183 12: 24389/16384 688.732 13: 12901781/8388608 745.280 14: 841/529 802.606 15: 841/512 859.154 16: 20511149/12058624 919.612 17: 471756427/268435456 976.160 18: 29/16 1029.577 29th harmonic 19: 707281/376832 1090.034 20: 16267463/8388608 1146.583 21: 2/1 1200.000 octave Interesting. No more than 6 cents away from 21-equal. Also points out a nice way of doing multiples of 3-equal...29/23. Fun, Jacob
From: monz (2004-07-23)
Subject: Re: 23-and-29 only, and sagittal ET notation
hi Jacob,
--- In [email protected], "Jacob" <jbarton@r...> wrote:
> First of all, has anyone noticed that 29/16 is one cent
> away from six steps of 7 equal?
> Ain't that something? Two implications I see:
>
> 1. 7 equal could be notated with ABCDEFG defined as a
> "circle" of sevenths, or seconds (32/29's), and its lower
> multiples with accidentals in accordance with some
> non-3 lattice.
>
> 2. In particular, a 21-note periodicity block in 23,29 only,
> defined by "unison vectors" 23^(-3)2*29^3 and 23^3 29^(-4):
>
> 0: 1/1 0.000 unison, perfect prime
> 1: 24389/23552 60.457
> 2: 560947/524288 117.006
> 3: 594823321/536870912 177.463
> 4: 841/736 230.880
> 5: 19343/16384 287.429
> 6: 20511149/16777216 347.886
> 7: 29/23 401.303
> 8: 707281/541696 461.760
> 9: 707281/524288 518.309
> 10: 374151649/268435456 574.857
> 11: 24389/16928 632.183
> 12: 24389/16384 688.732
> 13: 12901781/8388608 745.280
> 14: 841/529 802.606
> 15: 841/512 859.154
> 16: 20511149/12058624 919.612
> 17: 471756427/268435456 976.160
> 18: 29/16 1029.577 29th harmonic
> 19: 707281/376832 1090.034
> 20: 16267463/8388608 1146.583
> 21: 2/1 1200.000 octave
>
> Interesting. No more than 6 cents away from 21-equal.
> Also points out a nice way of doing multiples of 3-equal...29/23.
>
> Fun,
> Jacob
i made graphs a long time ago of chains of prime intervals.
i.e., a chain of 3/2s, of 5/4s, of 7/4s, of 11/8s, etc.
looks like i never put these on my website ... maybe if
i find them i can. they're in my book.
anyway, here's the list of monzos for your scale:
(in descending order as usual with me; on the Yahoo
interface, click "Reply" to view properly)
2,23,29-monzo
21: [ 1, 0, 0 >
20: [-23, 1, 4 >
19: [-14, -1, 4 >
18: [ -4, 0, 1 >
17: [-28, 1, 5 >
16: [-19, -1, 5 >
15: [ -9, 0, 2 >
14: [ 0, -2, 2 >
13: [-23, 2, 3 >
12: [-14, 0, 3 >
11: [ -5, -2, 3 >
10: [-28, 2, 4 >
9: [-19, 0, 4 >
8: [-10, -2, 4 >
7: [ 0, -1, 1 >
6: [-24, 0, 5 >
5: [-14, 1, 2 >
4: [ -5, -1, 2 >
3: [-29, 0, 6 >
2: [-19, 1, 3 >
1: [-10, -1, 3 >
0: [ 0, 0, 0 >
8ve-equivalent 23,29-primespace lattice:
(numbers are scale-degrees)
<<< 29 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
0 1 2 3 4 5 6
^ 2 ------------------13---10-------------
^ | | | | | | |
^ 1 --------------5----2---20---17-------
^ | | | | | | |
23 0 --0=21--18---15---12----9----6----3---
v | | | | | | |
v -1 ---------7----4----1---19---16--------
v | | | | | | |
v -2 -------------14---11----8-------------
-monz
From: monz (2004-07-23) Subject: Re: 23-and-29 only, and sagittal ET notation hi Jacob, --- In [email protected], "Jacob" <jbarton@r...> wrote: > > > 2. In particular, a 21-note periodicity block in 23,29 only, > > defined by "unison vectors" 23^(-3)2*29^3 and 23^3 29^(-4): are you sure about those unison-vectors? the first one is OK, but the second one looks a little strange. for one thing, it's missing 2^6, which it needs in order to be close to a unison. for another thing, it's bigger than 166 cents, which isn't much of a unison anyway. here's my tabulation of them: 2,23,29-monzo ratio ~cents [-1 -3 3 > 24389 / 24334 3.908540654 [ 6 3 -4 > 778688 / 707281 166.5142652 -monz
From: monz (2004-07-23) Subject: Re: 23-and-29 only, and sagittal ET notation hi Jacob, --- In [email protected], "monz" <monz@a...> wrote: > --- In [email protected], "Jacob" <jbarton@r...> wrote: > > > > > 2. In particular, a 21-note periodicity block in 23,29 only, > > > defined by "unison vectors" 23^(-3)2*29^3 and 23^3 29^(-4): > > > are you sure about those unison-vectors? > > the first one is OK, but the second one looks a > little strange. for one thing, it's missing 2^6, > which it needs in order to be close to a unison. > for another thing, it's bigger than 166 cents, > which isn't much of a unison anyway. > > here's my tabulation of them: > > 2,23,29-monzo ratio ~cents > > [-1 -3 3 > 24389 / 24334 3.908540654 > [ 6 3 -4 > 778688 / 707281 166.5142652 you meant for the second one to be this: [-33 3 4 > 7470507 / 7457005 3.131818418 or in your notation: 2^(-33) 23^3 29^4 -monz
From: monz (2004-07-23)
Subject: Re: 23-and-29 only, and sagittal ET notation
--- In [email protected], "monz" <monz@a...> wrote:
> hi Jacob,
>
>
> --- In [email protected], "monz" <monz@a...> wrote:
>
> > --- In [email protected], "Jacob" <jbarton@r...> wrote:
> > >
> > > > 2. In particular, a 21-note periodicity block in 23,29 only,
> > > > defined by "unison vectors" 23^(-3)2*29^3 and 23^3 29^(-4):
> >
> >
> > are you sure about those unison-vectors?
> >
> > the first one is OK, but the second one looks a
> > little strange. for one thing, it's missing 2^6,
> > which it needs in order to be close to a unison.
> > for another thing, it's bigger than 166 cents,
> > which isn't much of a unison anyway.
> >
> > here's my tabulation of them:
> >
> > 2,23,29-monzo ratio ~cents
> >
> > [-1 -3 3 > 24389 / 24334 3.908540654
> > [ 6 3 -4 > 778688 / 707281 166.5142652
>
>
>
> you meant for the second one to be this:
>
> [-33 3 4 > 7470507 / 7457005 3.131818418
>
>
> or in your notation: 2^(-33) 23^3 29^4
so the lattice would show the unison-vectors like this:
8ve-equivalent 23,29-primespace lattice:
(numbers are scale-degrees)
<<< 29 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
0 1 2 3 4 5 6
^ 3 ---------------------(0=21)-----------
^ | | | | | | |
^ 2 ------------------13---10-------------
^ | | | | | | |
^ 1 --------------5----2---20---17-------
^ | | | | | | |
23 0 --0=21--18---15---12----9----6----3---
v | | | | | | |
v -1 ---------7----4----1---19---16--------
v | | | | | | |
v -2 -------------14---11----8-------------
v | | | | | | |
v -3 ----------------(0=21)----------------
-monz
From: Jacob (2004-07-24) Subject: Re: 23-and-29 only, and sagittal ET notation --- In [email protected], "monz" <monz@a...> wrote: > hi Jacob, > > > --- In [email protected], "monz" <monz@a...> wrote: > > > --- In [email protected], "Jacob" <jbarton@r...> wrote: > > > > > > > 2. In particular, a 21-note periodicity block in 23,29 only, > > > > defined by "unison vectors" 23^(-3)2*29^3 and 23^3 29^(-4): > > > > > > are you sure about those unison-vectors? > > > > the first one is OK, but the second one looks a > > little strange. for one thing, it's missing 2^6, > > which it needs in order to be close to a unison. > > for another thing, it's bigger than 166 cents, > > which isn't much of a unison anyway. > > > > here's my tabulation of them: > > > > 2,23,29-monzo ratio ~cents > > > > [-1 -3 3 > 24389 / 24334 3.908540654 > > [ 6 3 -4 > 778688 / 707281 166.5142652 > > > > you meant for the second one to be this: > > [-33 3 4 > I sure did. But I get 8605487927/8589934592, not > 7470507 / 7457005 > Weird. But, yeah. Typo. Jacob
From: Petr Parízek (2004-07-24) Subject: Re: [tuning] 23-and-29 only, and sagittal ET notation From: "Jacob" <jbarton@r> > First of all, has anyone noticed that 29/16 is one cent away from six steps of 7 equal? > Ain't that something? Great. It's just as you said. 32/29 is about a cent flatter than one step of 7-equal, and therefore, of course, (32/29)^14 is 14 cents flatter than 2 octaves. And what about the fact that 39/32 is close to two steps of 7-equal? If you're interested, I can tell you that (39/32)^7 is only ~2.6 cents flatter than 2 octaves (or 13^7 * 3^7 / 2^37). So if I wanted to make something like a 7-tone well-temperament, I'd definitely go this way. Incidentally, your idea of approximating 7-equal made me write a new scale approximating 12-equal (maybe Monz could be interested). Unlike my previous scales approximating 12-equal, this one does not use such primes as 17 or 19. On the other hand, I managed to use the primes of 7 and 11 here, which are not found in any of the previous rational well-temps. How did I get it? Just like this: ! 11lwt.scl ! 11-limit Rational Well-temperament 12 ! 1323/1250 55/49 297/250 63/50 4/3 99/70 220/147 100/63 42/25 5500/3087 66/35 2/1 Petr