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19-limit miracle

🔗Gene Ward Smith <gwsmith@svpal.org>

7/6/2003 2:19:37 AM

I was pondering the 351/350 comma, which allows the 1--9/7--20/13 triad
to be considered as having a 6/5 from 9/7 to 20/13. This is a feature
of 13-limit meanpop, and hence my "ratwolf" and what one might call
"wilwolf", which is meanpop[12] using a Wilson fifth. It's also a
feature of the logical extension of 11-limit miracle to 13-limit; one
adds 351/350 to <225/224, 243/242, 385/384> and gets a 13-limit
version of miracle which 72-et supports, but for which 175--which is
poptimal--is a much better choice. We pick the second-best tuning for
13, and [175, 277, 406, 491, 605, 647] works out nicely. It also
extends naturally to a 19-limit version,
[175, 277, 406, 491, 605, 647, 715, 743]. A comma basis for this is
[225/224, 243/242, 273/272, 324/323, 351/350, 375/374, 1445/1444]. If
we leave off the 1445/1444 we get a basis for the 19-limit miracle,
but really there seems little point in trying to separate this from
175, any more than much is to be gained by prying 11-limit miracle
away from 72.

It might be interesting to explore some of the Fokker blocks these
comma sets lead to.

🔗Dave Keenan <D.KEENAN@UQ.NET.AU>

7/7/2003 3:45:58 PM

So Gene,

What is the mapping from generators to primes and what are the errors?

🔗Gene Ward Smith <gwsmith@svpal.org>

7/7/2003 6:36:36 PM

--- In tuning-math@yahoogroups.com, "Dave Keenan" <D.KEENAN@U...> wrote:

> What is the mapping from generators to primes and what are the errors?

Mapping to primes:
[[1, 1, 3, 3, 2, 7, 7, -1], [0, 6, -7, -2, 15, -34, -30, 54]]

Errors of the primes, in cents:
[-2.52, -2.32, -1.97, -2.76, -3.96, -2.09, -2.66]

commas: [225/224, 243/242, 273/272, 324/323, 351/350, 375/374]
(Since this is in effect 175-et, we may want to add 1445/1444)

175-et val: [175, 277, 406, 491, 605, 647, 715, 743] (not "standard")

rms secor: .09714280747968 = 16.999991308944 / 175

🔗Dave Keenan <D.KEENAN@UQ.NET.AU>

7/7/2003 7:02:24 PM

--- In tuning-math@yahoogroups.com, "Gene Ward Smith" <gwsmith@s...>
wrote:
> --- In tuning-math@yahoogroups.com, "Dave Keenan" <D.KEENAN@U...> wrote:
>
> > What is the mapping from generators to primes and what are the errors?
>
> Mapping to primes:
> [[1, 1, 3, 3, 2, 7, 7, -1], [0, 6, -7, -2, 15, -34, -30, 54]]
>
> Errors of the primes, in cents:
> [-2.52, -2.32, -1.97, -2.76, -3.96, -2.09, -2.66]
>
> commas: [225/224, 243/242, 273/272, 324/323, 351/350, 375/374]
> (Since this is in effect 175-et, we may want to add 1445/1444)
>
> 175-et val: [175, 277, 406, 491, 605, 647, 715, 743] (not "standard")
>
> rms secor: .09714280747968 = 16.999991308944 / 175

I'm afraid that jump in complexity from 22 to 49, in going from
11-limit to 13-limit, (and then 88 for 19-limit) makes it fairly
uninteresting, except perhaps as a way of mapping higher primes to a
miracle (decimal) keyboard.

🔗Gene Ward Smith <gwsmith@svpal.org>

7/8/2003 3:56:47 PM

--- In tuning-math@yahoogroups.com, "Dave Keenan" <D.KEENAN@U...>
wrote:

> I'm afraid that jump in complexity from 22 to 49, in going from
> 11-limit to 13-limit, (and then 88 for 19-limit) makes it fairly
> uninteresting, except perhaps as a way of mapping higher primes to a
> miracle (decimal) keyboard.

This more or less says that 19-limit temperaments are never
interesting.