dinky but fun web-based virtual improvisor.

Hey folks, I was learning "php," the web-app language, and I did this
"virtual improvisor" that takes any scale, does some freaky stuff with
it, and jams:

http://music.columbia.edu/~chris/lsys.html

Try it. I think it's fun (at least the first couple of times) and
generates somewhat interesting tunes. (mp3's of about 1 minute in length).
Let me know if there's stuff you can't figure out or instructions that
don't make sense or whatever----also, I don't do much (actually no)
error-checking in the thing, so follow the instructions carefully. (life
is short).

explanation:

Theory:

Basically, the way it works is this.

You enter a scale---via ratios or cents notation.
First it constructs an "ornamentation tree." I.e. each note of the scale
is going to have a few notes that form a "neighbor-formation" attached to
that given note. Sometimes a note has several different
"neighbor-formations" attached to it. It takes little randomly chosen
chunks of the scale--2 or 3 notes (or rather, intervals) (maybe even 4 or
5) and these become the neighbor-formations. Then, it might attach
neighbor-formations to each of the notes of the previous level of
neighbor-formation. And, it may go down another level(s) in addition,
though this becomes less and less likely.

Hence a "tree" of neighbor-formations is formed---a space for
improvisation or composition.

Example:
C-Db-Eb

It might attach, to Db: Db-D, and Db-D-E, and Db-Eb

Then, to #2 above, it might attach to the D, D-Eb-F and D-E.

and so on.

Then, an "improviser" comes along and plays through the tree, at random.
The rule is that when it goes "into" a neighbor-formation, it must
eventually return to the neighbored-note. (Though it may nest further
into the tree beforehand.) Currently, I have the rhythms set up so that
the farther into the "branches" of the tree the tune goes, the shorter the
durations, the more rapid the flow of notes.

********************************

Christopher Bailey

http://music.columbia.edu/~chris

********************************

Christopher Bailey wrote,

> Try it. I think it's fun (at least the first couple of times)

Yeah, that really says it all... After initially having a dyslectic
moment and typing in a numerically reversed cents value, I tried the
same scale again, and both the wrong and the right ones are equally
fun -- well, "at least the first couple of times"!

neat,

--Dan Stearns

>From: Christopher Bailey <cb202@columbia.edu>
>
>You enter a scale---via ratios or cents notation.
>First it constructs an "ornamentation tree." I.e. each note of the scale
>is going to have a few notes that form a "neighbor-formation" attached to
>that given note.

Have you looked at the work of David Cope? In particular
"Computers and Musical Style" and "Experiments in Musical
Intelligence" might provide some interesting approaches to these
ornamentation trees of yours.

http://arts.ucsc.edu/faculty/cope/

He has the code from his articles and books at his web page,
but they might be a bit opaque without the accompanying text, and
they're written in Lisp, a beautiful programming language that has
never been exactly popular.

--
William S. Annis wsannis@execpc.com
Mi parolas Esperanton - La Internacian Lingvon www.esperanto.org

i'm a friend of David Cope. if anyone needs a specific question
answered, i'd be happy to ask him for you (he is extremely busy so please
make your questions brief and to the point).

also,

can anyone refer me to some good websites for Yamaha TX81Z tuning tables?

best,

brian rabben

Chris-

I really wanted to try this with a decatonic scale, so I chose 9 under

"How many numbers will you be entering below? (This should come out to be
the number of notes in the scale, minus the tonic, and not including the
upper octave of the tonic either):"

but there were only 8 spaces below that.

:(

-Paul

--- In tuning@egroups.com, Christopher Bailey <cb202@c...> wrote:

http://www.egroups.com/message/tuning/14504

>
> Hey folks, I was learning "php," the web-app language, and I did
this "virtual improvisor" that takes any scale, does some freaky
stuff with it, and jams:
>
> http://music.columbia.edu/~chris/lsys.html

I got a "method not allowed," "no posting allowed" error message when
I tried this... so, so much for this excitement...

__________ ____ __
Joseph Pehrson