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chain-of-minor-third scale revisited

🔗Paul Erlich <paul@stretch-music.com>

9/24/2001 3:15:00 PM

Earlier this year, Graham Breed performed a computer search for
the "best" linear temperaments. "Best" is roughly defined as meaning
the greatest number of complete, consonant chords, tuned as closely
to JI as possible, for a given number of notes in a melodically
coherent scale (MOS, with interval of repetition equal to the octave,
or one-half octave, or one-third octave, etc). His search was
performed by "cross-Breeding" a selection of consistent ETs in
various ways.

One might have expected the #1 rank in the 5-limit to go to meantone
temperament, with its richly harmonizing diatonic and chromatic
scales. But meantone is actually only #2!

#1 is the Stearns/Breed/Keenan chain-of-minor-thirds temperament. The
generator is a minor third of 317 cents. Thus it is approximated
quite well 19-tone equal temperament. There is a 7-tone MOS, which in
19-tET has steps 1 4 1 4 4 1 4, or degrees 0 1 5 6 10 14 15 (19). A
bit of music in this scale can be heard here:

http://www.angelfire.com/mo/oljare/images/skopnytt.mid

A lattice reveals the major and minor triads:

15
\
\
\
\
1
/ \
/ \
/ \
/ \
14---------6
\ /
\ /
\ /
\ /
0
\
\
\
\
5

There are only two complete triads here. Why does this beat meantone,
where a 7-tone scale has six complete triads? Because the maximum
error from JI here is 1.4 cents -- almost four times less than the
maximum error in meantone. More triads can be found in the next-
higher MOS, an 11-tone one, which gives four additional major and
four additional minor triads. The scale in 19-tET has steps of 1 3 1
1 3 1 1 3 1 1 3, or scale degrees 0 1 4 5 6 9 10 11 14 15 16 (19).
The lattice:

10
/ \
/ \
/ \
/ \
4--------15
\ / \
\ / \
\ / \
\ / \
9---------1
\ / \
\ / \
\ / \
\ / \
14---------6
\ / \
\ / \
\ / \
\ / \
0--------11
\ / \
\ / \
\ / \
\ / \
5--------16
\ /
\ /
\ /
\ /
10

It's latticed and explored in greater detail, including 9-limit
considerations, at
<http://www.uq.net.au/~zzdkeena/Music/ChainOfMinor3rds.htm>). This
scale, though, is highly improper, with many of the "thirds" smaller
than many of the "seconds" . . .

🔗Paul Erlich <paul@stretch-music.com>

9/25/2001 12:36:02 PM

--- In tuning@y..., "D.Stearns" <STEARNS@C...> wrote:
> Paul,
>
> I'm not sure if I had anything to do with the origins of this scale
or
> not... I forget (Dave Keenan has a beautiful page on it).
>
> However, I did post on the [7,4] 11-tone quite a bit, and another
way
> to possibly think of this in a 5-limit context is as a chain of 5/3s
> that when converted from 1D to 2D becomes somewhat analogous to the
> 7-tone 4:5:6, only here it's an 11-tone 3:4:5.
>
> So tempering out the 15625/15552 theoretically gives five consonant
> (or alike) 3:4:5s and four

five?

> alike 1/(5:4:3)s.
>
> Here's the 2D 7-tone MOS,
>
> (*)--*---*---*
> \ / \
> *---*---*---*
>
> and here's the 2D 11-tone MOS,
>
> (*)--*---*---*---*---*
> \ / \ / \ / \ / \ / \
> *---*---*---*---*---*
>
>
> --Dan Stearns

Isn't this exactly what was in my post? What new insight have you
added -- I'm missing it.
>
> (btw, I liked the 22-tet microfest mp3s John Starrett posted earlier
> today, especially the '60s-ish pop ballad one)

Which one is that??

🔗Latchezar Dimitrov <latchezar_d@yahoo.com>

9/25/2001 4:37:05 PM

Sorry, but MINOR or MAJOR third's have never be one
interval referance or one just intonation intervals
!!!
It's one completly wrong way to follow !
The third is and has everytime one non consonant
interval ! Remember it, pls :)
And stop to go to...nothing!

Dimitrov :)

--- Paul Erlich <paul@stretch-music.com> a �crit�: >
--- In tuning@y..., "D.Stearns" <STEARNS@C...>
> wrote:
> > Paul,
> >
> > I'm not sure if I had anything to do with the
> origins of this scale
> or
> > not... I forget (Dave Keenan has a beautiful page
> on it).
> >
> > However, I did post on the [7,4] 11-tone quite a
> bit, and another
> way
> > to possibly think of this in a 5-limit context is
> as a chain of 5/3s
> > that when converted from 1D to 2D becomes somewhat
> analogous to the
> > 7-tone 4:5:6, only here it's an 11-tone 3:4:5.
> >
> > So tempering out the 15625/15552 theoretically
> gives five consonant
> > (or alike) 3:4:5s and four
>
> five?
>
> > alike 1/(5:4:3)s.
> >
> > Here's the 2D 7-tone MOS,
> >
> > (*)--*---*---*
> > \ / \
> > *---*---*---*
> >
> > and here's the 2D 11-tone MOS,
> >
> > (*)--*---*---*---*---*
> > \ / \ / \ / \ / \ / \
> > *---*---*---*---*---*
> >
> >
> > --Dan Stearns
>
> Isn't this exactly what was in my post? What new
> insight have you
> added -- I'm missing it.
> >
> > (btw, I liked the 22-tet microfest mp3s John
> Starrett posted earlier
> > today, especially the '60s-ish pop ballad one)
>
> Which one is that??
>
>

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🔗Paul Erlich <paul@stretch-music.com>

9/26/2001 10:08:43 AM

--- In tuning@y..., "D.Stearns" <STEARNS@C...> wrote:

> <<Isn't this exactly what was in my post? What new insight have you
> added -- I'm missing it.>>
>
> Well my point for whatever it's worth was that you could base it on
> the 3:4:5

Don't know what that means (as opposed to basing it on the 4:5:6),
but I'm confident that your way of seeing it is as good as any. If
you'd care to elaborate in as simple terms as you can, I'd welcome it.

> so that it's a PB where the UVs are 15625/15552 and
> 16/15--or did you already mention that!

I didn't mention that, and it's very important -- thanks! In
particular, the kleisma or 15625/15552 is tempered out (so it's the
commatic unison vector), while 16/15 is not (so it's the chromatic
unison vector).

> >
> > Which one is that??
>
>
> One of them.
>
Sorry -- what was the context?

🔗Paul Erlich <paul@stretch-music.com>

9/26/2001 10:10:19 AM

--- In tuning@y..., Latchezar Dimitrov <latchezar_d@y...> wrote:
> Sorry, but MINOR or MAJOR third's have never be one
> interval referance or one just intonation intervals
> !!!

What do you mean?

> It's one completly wrong way to follow !
> The third is and has everytime one non consonant
> interval !

The third is non consonant?

> Remember it, pls :)
> And stop to go to...nothing!

Thanks for your open-mindedness.