Just Guitar

Guitarists:

I've discovered a way to use any guitar, even one fretted to 12 EDO, to explore certain types
of JI scales. I should say at the outset that the restrictions are pretty severe. Basically,
you can get certain tetrachordal, heptatonic scales, and their modes, with a drone. With some
thought, that could be expanded somewhat within the confines of the principle behind the
trick. At least it allows some experimentation in JI to those guitarists among us who can't
afford to have a guitar fretted to JI yet. Here's the method/trick:

Leave your D string at D or maybe as much as a whole tone lower. Tune the A string up to one
scale degree below the D string. Tune the G, B, and high E strings to consecutive scale
degrees - in other words, tune everything except the low E as if you were tuning up a diatonic
harp. Tune the low E string down to a drone tone, usually the tonic of whatever scale you have
chosen. Use string harmonics to achieve (practically) Just relationships between all strings.

Now pluck the harmonics at the half and third positions of the 5 scale-degree-tuned strings.
Since the third position harmonics are (obviously) 3/2 above the half position, the lower
tetrachord will be available at the half position, and will duplicate itself a perfect fifth
above at the third position, making a complete tetrachordal scale. Obviously, you've got the
quarter position, too, simply adding another three notes of range. Isn't there a name for
this, when the lower and upper tetrachords of a scale contain the same intervals in the same
order? Iso-somethingorother?

Anyway, I've found it really enjoyable to play this way. If you grow your right hand nails out
a bit, it's easy to get used to playing all harmonics with four fingers on five strings, and
periodically thumbing the drone. Naturally, it's prone to medieval sounding music, my chief
interest at present. Once I get a break from my nightmarish schedule, I'll try to record and
post some examples. Might be a few weeks.

--
David J. Finnamore
Nashville, TN, USA
http://members.xoom.com/dfinn.1
--

--- In tuning@egroups.com, "David J. Finnamore" <daeron@b...> wrote:
> Guitarists:
>
> I've discovered a way to use any guitar, even one fretted to 12
>EDO,
>to explore certain types
> of JI scales.
><snip> Here's the method/trick:
>
> Leave your D string at D or maybe as much as a whole tone lower.
>Tune the A string up to one
> scale degree below the D string. Tune the G, B, and high E strings
>to consecutive scale
> degrees - in other words, tune everything except the low E as if
>you were tuning up a diatonic
> harp. Tune the low E string down to a drone tone, usually the
>tonic of whatever scale you have
> chosen. Use string harmonics to achieve (practically) Just
>relationships between all strings.
>
> Now pluck the harmonics at the half and third positions of the 5
>scale-degree-tuned strings.
> Since the third position harmonics are (obviously) 3/2 above the
>half position, the lower
> tetrachord will be available at the half position, and will
>duplicate itself a perfect fifth
> above at the third position, making a complete tetrachordal scale.
>Obviously, you've got the
> quarter position, too, simply adding another three notes of range.
<snip>
> David J. Finnamore

Nice trick. The same sort of scale structure can be played on a bass
guitar (especially with round-wound strings) without retuning, since
the mass of the strings makes higher harmonics easier to produce.
Locate the third, fourth and fifth harmonic on one of your strings
(the third harmonic is almost right over the fifth fret on a 12tet
guitar or bass, while the fourth and fifth are roughly over the
fourth and third fret). These three form a just major triad 1/1 5/4
3/2, and on a 4 string bass there are four of these a fourth apart.
Here is the basic scale pattern, with the degrees from 1 to 10:

3 4 5 fret number
| | |
G 10 8
/ /
D 9 7 5
/ /
A 6 4 2
/ /
E 3 1

Using the triad 5/4 3/2 7/4 and the same fingering pattern, down
roughly 1 fret results in a different scale.

The first scale is the basic scale used by the late Jaco Pastorius on
his solo piece Portrait of Tracy from his debut album.

John Starrett wrote,

>The first scale is the basic scale used by the late Jaco Pastorius on
>his solo piece Portrait of Tracy from his debut album.

Thanks for that! Is this _Jaco Pastorius_, 1976?

--- In tuning@egroups.com, "Paul H. Erlich" <PERLICH@A...> wrote:
> John Starrett wrote,
>
> >The first scale is the basic scale used by the late Jaco Pastorius
on
> >his solo piece Portrait of Tracy from his debut album.
>
> Thanks for that! Is this _Jaco Pastorius_, 1976?

Yup. I heard Portrait of Tracy on the radio as I was waking up one
day, went out and bought the album, and pulled out all my frets that
afternoon. What a great album that is!

John Starrett wrote:

> The same sort of scale structure can be played on a bass
> guitar (especially with round-wound strings) without retuning, since
> the mass of the strings makes higher harmonics easier to produce.

A-ha! Great idea. Now I need an acoustic bass. :-) Guess I'll start practicing on my electric
(with frets).

--
David J. Finnamore
Nashville, TN, USA
http://personal.bna.bellsouth.net/bna/d/f/dfin/index.html
(Those of you who have visited my mostly Tolkien-related site in the past, only to be frustrated
by xoom.com's flaky servers, I've now moved it. Should load up consistently now.)
--