CA/CB

Hi Chris
greetings to you
as you appear to have a Mac, and although it is midi only,
you might be interested in Paul Webb's shareware, particularly Cellular Grid
Machine.
http://www.robotsoftware.co.uk.
This uses an 8x8 2D CA as an 8 track sequencer that can operate in either or
both of two perpendicular directions.

Good to see someone thinking out loud about these things, also very good
that you're exploring the synthesis of theory, sound manipulation,
algorithms, tuning and good ol' music making itself.
This is good for a group's community spirit, and I'm sure will stimulate
even lurkers (how about renaming lurkers?).

Enjoyed your spaceship piece - a lot of really fresh energy happening - one
part of it reminded me of Daniel Lentz's music which I like a lot.
Strangely some of John Conway's Life CA's are both self-sustaning and also
emit self-sustaining "entities" called spaceships!

looking forward to your future thinking, loud and soft,

LAWRENCE BALL-
composer
math tutor
director, Planet Tree Music Festival http://www.planettree.org

Message: 17
Date: Tue, 30 Jan 2001 23:01:21 -0500 (EST)
From: Christopher Bailey <cb202@columbia.edu>
Subject: cellular automata

R Walker wrote:
>Another idea: the timbre varies for each note of the mode, depending on
>which
>cells are
>occupied in its row (and the only ones played are the ones with at least
>one
>cell
>occupied).

Yeah, when doing anything with computer music, I always try to err on the
side of constantly changing timbres.

Therefore, your original idea, if I understand correctly, would present a
series of "Frames." Each "frame" (based on a generation of CA) would
present a mode and a timbre for improvisation/composition.
But my gut reaction would be to have the timbre changing much faster than
the mode.

I guess one could run through the generations much faster for the
timbre--like, one generation per note. For the modes, it could be
happening a lot slower. Hey, since all CA's repeat themselves eventually,
or eventually end up in repeating cycles, we'd end up with some kind of
isorhythm, as a set of timbres were "cycled" through, and a set of modes
were "cycled" through, but at different rates. Could be cool.

Also, we could make use of the extra dimension in determining timbre.
Timbre is not only determined by partials and their strengths, there are
also such issues as attack strength, agitation during steady state (i.e,
vibrato or tremolo), release, amount of change in brightness---plus lots
of other quirky parameters that one can almost invent.

One could specify "areas" of a 2D CA. Each area (say, a 4X4 square) could
be converted into a number (via binary arithmetic), which would then
control the value of some timbral parameter. For each note (i.e. for each
CA generation) then, the parameters would be re-calculated. Each note
could then be individually sculpted according to its parameters.

Of course, one would have to find the right kind of CA for this---most 2D
CAs end up very soon with, like, a squiggly monster in the middle and not
much happening anywhere else---which would mean in sound, that those notes
would have most of their parameters remaining constant, with very few
changing. One would have to find a CA with lots of activity all over the
place for a good long time.

Anyway, just thinking out loud. . . .

CB