Experiment for Paul Erlich [12-22 tone]

> Well mine is not just of course, with its 17-cent errors and all.
> Once you have the erl.kbm scale tuned right, try dominant sevenths
> with the root, fifth, and seventh on one color and the third on the
> other color (I'm talking about white keys and black keys as the two
> colors). Then try the mirror versions of those chords (i.e., the way
> they would appear in a mirror placed next to your keyboard). What is
> your reaction? Do you like them better than in 12-tET? Try the other
> tetrads -- do some sound more dissonant to you? Do a few of them
> sound almost consonant?
>

Hi Paul!

Well, finally I tuned up your 12 out of 22 scale properly and this is my
result:

I was able to use exactly the same patch for the "new" 12-tone scale as
a 12t-ET patch, so I could compare the chords right away...

I find when I play a 7th chord on the black notes... let's say
Eb-Gb-Bb-Db, the 22-12 scale sounds slightly more "dissonant" than the
12t-ET version (!) I think it is the smaller minor third Eb-Gb, which I
am not used to. Is that really supposed to be smaller?? It sure sounds
like it.. But the minor third in just is larger?? Or isn't this just??

HOWEVER, the MAJOR 7th chord... Eb-G-Bb-Db seems almost BEATLESS in the
22-12 version, wheras the 12t-ET version has beating. Is the major
third SMALLER than in 12t-ET? I guess if it is, it is this just 7th
that is creating this beatless effect.

These similar effects are observed if I just play the triads, WITHOUT
the 7ths... but the effects are not as pronounced.

Are these the chords I should be trying... or should I be trying
something else... and do my results make sense??

Thanks!

__________ ______ ___ __ _
Joseph Pehrson

--- In tuning@egroups.com, Joseph Pehrson <josephpehrson@c...> wrote:
> > Well mine is not just of course, with its 17-cent errors and all.
> > Once you have the erl.kbm scale tuned right, try dominant
sevenths
> > with the root, fifth, and seventh on one color and the third on
the
> > other color (I'm talking about white keys and black keys as the
two
> > colors). Then try the mirror versions of those chords (i.e., the
way
> > they would appear in a mirror placed next to your keyboard). What
is
> > your reaction? Do you like them better than in 12-tET? Try the
other
> > tetrads -- do some sound more dissonant to you? Do a few of them
> > sound almost consonant?
> >
>
> Hi Paul!
>
> Well, finally I tuned up your 12 out of 22 scale properly and this
is my
> result:
>
> I was able to use exactly the same patch for the "new" 12-tone
scale as
> a 12t-ET patch, so I could compare the chords right away...
>
> I find when I play a 7th chord on the black notes... let's say
> Eb-Gb-Bb-Db, the 22-12 scale sounds slightly more "dissonant" than
the
> 12t-ET version (!)

Joseph, that's not one of the chords I was referring to above, because
(a) it's a m7 chord, and not a dom7 or half-dim7th, in 12-tET.
(b) all the keys are the same color (black, in this case).

> I think it is the smaller minor third Eb-Gb, which I
> am not used to. Is that really supposed to be smaller?? It sure
sounds
> like it.. But the minor third in just is larger?? Or isn't this
just??

The chord you played is actually an approximation of 12:14:18:21, an
interesting chord in its own right (do a search...). The usual "just"
minor seventh chord, though is 10:12:15:18 (and yes, its minor thirds
are wider than 12-tET minor thirds), which can also be found in my
mapping, at any place where the root and fifth are one color, and the
third and seventh are the other color.

> HOWEVER, the MAJOR 7th chord... Eb-G-Bb-Db seems almost BEATLESS in
the
> 22-12 version, wheras the 12t-ET version has beating. Is the major
> third SMALLER than in 12t-ET?

Yes, the major third in 22-tET is very close to the just major third.

> I guess if it is, it is this just 7th
> that is creating this beatless effect.

Huh? I would say that the two nearly just major 3rds are far more
important than the major 7th in creating this beatless effect.

--- In tuning@egroups.com, Joseph Pehrson <josephpehrson@c...> wrote:
> HOWEVER, the MAJOR 7th chord... Eb-G-Bb-Db seems almost BEATLESS in
the
> 22-12 version, wheras the 12t-ET version has beating.

Wait a minute -- Eb-G-Bb-Db is not a MAJOR 7th chord! You must have
been actually either talking about the major 7th chord Eb-G-Bb-D, or
the dominant 7th chord Eb-G-Bb-Db. I assumed the former in my last
post, but if it was the latter, you were actually following my
original prescription of what to try. Which was it?