Aleatoric Tuning Methods, Part II - Xylophones

Hi all!

Which brings us to a few weeks ago...

I was building some elaborate shelves in the garage out of
2x4s and 2x6s (a 2 by 4 is a board 1.5 by 3.5 inches by
however many feet long and is used in framing houses most
commonly) made of Douglas Fir, a local softwood.

At some point I was playing with an 8 foot long 2x4 that
had really good straight grain with no knots, but was
warped. I noticed that it had a very nice sound when I
thunked it. I suspended it over two cardboard boxes and
played it for a while, noticing the wide variety of sounds
I was able to get out of it.

Then I noticed that it happened that many of the crossbar
pieces for the shelves, as well as some leftover scraps,
were between 18 and 27 inches long.

I laid out a couple of long boards in a nonparallel
configuration and then started placing the smaller boards
on top of this. I adjusted the positions of the smaller
boards while thunking them until I got the best tone. Some
of the boards did not sound as good, and I put them aside
to be the actual ones that would be used in the shelves.
Then I raised the bass end up various heights until I
found the height that made the sound loudest from the
sound waves going down to the concrete garage floor and
back -- so the open space below the xylophone served as a
simple resonator.

Then I went and got some mallets - both solid wood, and
wood covered at the end with tightly wrapped rubber
innertube.

And played the xylophone.

And it sounded _really_ good - I mean great, absolutely
fantastic. The tuning was just like a gamelan tuning and
the tone was reminescent of Jegog of Negara. In fact, I
probably could not have come up with a better tuning
myself. And no, I will not list it in cents values. The
whole idea here is it is random. Everyone should build
their own shelves! Or perhaps you will be putting in some
copper pipes and have some copper tubing scraps left over,
or what have you. You don't need to construct formulas and
mathematical theories and cut things to precise lengths
and meticulously adjust them to just the right pitch. Not
unless you want to. What I am saying is you can get just
as good results by randomly picking up pieces of wood
scraps and arranging them.

The chickens heard me playing and wandered into the garage
and watched me playing, happily excited and mesmerized. I
knew that chickens liked _harmonic_ sounds like singing
and humming and speaking to them in a sing-song voice. But
the xylophone was definately not harmonic. It was quite
inharmonic and also very percussive and quite loud... just
the sort of thing you would thing a chicken would not
like. But they definately liked the music. In fact, they
were crazy about it. I tried different styles and found
that they liked it regular. If the rhythm or melody got
erratic, they became alarmed. They had different reactions
to different melodies. One of the hens sat down in front
of me and tried to lay an egg. This was extremely unusual
behavior -- hens like privacy, quiet and darkness to lay
their eggs. They can not *stand* to have someone watch
them when they are trying to lay an egg and will actually
blush if that happens. But this hen seemed to want my
attention, wanted me to notice that she was trying to
present an egg because of her respect and admiration for
the xylophone. After I went inside, the hen went into the
newspaper bin sitting on a shelf above the xylophone and
laid an egg there.

- Jeff

--- In tuning@y..., "J Scott" <xjscott@e...> wrote:

/tuning/topicId_22446.html#22446

> I was building some elaborate shelves in the garage out of
> 2x4s and 2x6s (a 2 by 4 is a board 1.5 by 3.5 inches by
> however many feet long and is used in framing houses most
> commonly) made of Douglas Fir, a local softwood.
>
> At some point I was playing with an 8 foot long 2x4 that
> had really good straight grain with no knots, but was
> warped. I noticed that it had a very nice sound when I
> thunked it. I suspended it over two cardboard boxes and
> played it for a while, noticing the wide variety of sounds
> I was able to get out of it.

Hi Jeff,

Thanks for pointing out how easy it can be to make a
decent-sounding instrument!

Jonathan Glasier created an instrument very similar to this
which he calls the "planks-a-lot" (Jonathan is very fond of,
and very good at, creating puns). It's simply a bunch of
different-length 2x4s tied together with rope. So it's
extremely portable (just an armful of wood and string),
and can then be lain down on a towel on any hard surface
and played like a marimba.

I got a chance to do some serious jamming on it back in
January at an awesome percussion improv session at Club Xanth
here in my neighborhood, which I'm *really* sorry we didn't
record.

I have a bit of personal experience in this too, having
easily modified a regular acoustic guitar into my "Rational
Guitar" by sanding the frets down flush with the fingerboard
and simply pasting a paper diagram onto the fingerboard
which had the fret placements marked and ratios written
next to them. Then I put plastic laminate over that,
and broke toothpicks into small enough pieces to make
individual frets, and glued them on. And so I had (and
still have) a guitar which could play all harmonics from
the 4th to the 27th (some of them adjusted to a "wrong"
"octave").

The biggest disadvantage is that the guitar is tuned entirely
to one key, the 1/1-otonality, and so the only way I can
modulate with the same interval structures is to go into
3/2-otonality and to a more limited extent to 9/8- and
5/4-otonalities. I had an earlier design that gave the
entire 11-limit tonality diamond, but I changed my mind,
now to my regret. But the guitar as it stands gives me
interesting "new" harmonic structures when I modulate into
other keys and only have harmonics of 1/1 available.

Hmmm... I suppose it should have been named "Harmonic Guitar"
instead...

-monz
http://www.monz.org
"All roads lead to n^0"