Thanks for you interest Andy! I must say, I appreciate all the work
that you have shared; it's been helpful to me in learning Pd.

The rubber band sound is a 3 dimensional physical model of a rubber
band that I made in matlab and ported to Pd. No, I'm just kidding, of
course you are right, it is a variable delay! That's a comb filter
(that Derek Holzer posted to the list a couple of years ago, as I was
getting started with this stuff) with a lop~ added to the feedback
loop. The input to the comb is a piezo pickup, which is mounted to a
shaker, which creates a second feedback loop. So the action of the
controller is integral to the sound synthesis, which is why it is
hard to tease out what is Pd and what is the controller. However,
without Pd running, the controllers can only make little scrapes and
crackles, really.

The principle behind the r.t.k. is this: the capacitance of 2
parallel plates is proportional to their surface area, and inversely
proportional to the distance between them. (now I'm not kidding!)
The tape knife constitutes one of the plates of the capacitor, and
there is an array of receiving antennas behind the playing surface
that constitutes the other. This array is laid out in such a way that
you can calculate the position of the tape knife based on their
relative capacitances. A very clever system for which I can take no
credit. See Max Mathews' Radio Baton.

foamboil- real water, coffee cup, drinking straw, microphone. I wrote
this to a table at 96,000 samples/second, so I could read it back
really slowly. Delay based panning only, which I think gives it sort
of a unreal sense of space.

As to which parts of my work use Pd, well it is pretty central! I use
[comport] to connect the microcontrollers to my laptop, all the
sensor data is conditioned and mapped in Pd to control parameters of
sounds that either originate in Pd or are processed by Pd.

You can browse the patches I'm using tomorrow, if you care to (dirty
laundry included) here and any comments would of course be very welcome:

http://idisk.mac.com/coldham-Public

(foam/stone.pd is the top patch.)

yours truly, Collin Oldham http://homepage.mac.com/coldham/klang