> An artist I know has created a sculpture consisting of a several
> kilometers of pink wire rolled into a giant sphere of about 90cm
> diameter.

Is this wire electrically one piece - IOW is it all welded together ?
If so, you will have to add sensor wires of your own. I'd expect
those sensors would be compromised by such a large mass of
metal around them though

> Theremin sounds aren't exactly what she wants - its the
> gestural interactivity that is the important bit

At one time I too was asked about an interactive sculpture
and did some research into Theremins. There is a lot of
information around, as you've probably found out. Three
people I'd suggest you Google search for +theremin are
Clara Rockmore, Fred Nachbaur and Robert Moog. Most
of the circuits I found are valve - I think I found just two
solid state circuits and one of those IIRC was from the
University Of Glasgow

>.Is this likely to be possible? I don't know much about what
> properties aerials have to have to make them work, will
> any old bit of wire do the job ?

You might be better to look around for an RF alarm circuit.
I ended up using a 300MHz oscillator with a 1ft aerial and
amplifying the amplitude changes into an ADC to control
lighting. A single wire will give better spatial effects than a
a single hemispherical tangle of wire, I think. The HF osc
was a very simple 2-transistor thing. Basically you have
two aerials - one on the PCB as a reference and one in
free air. As the one in free air is interfered with it creates
a difference signal with the reference one. Any HF osc
is sensitive to bodiliy capacitance. I've made many touch
sensors using 80kHz from a 4001

> Have also been considering hiding infrared proximity
> detectors under the wire and using them to trigger/ increase
> volume of sound stored on a chipCorder device

That would work. You can buy domestic security lights very
cheaply these days. In fact I would not buy PIR units from
an alarm or electronics company - I'd get a whole twin-light
unit from a discount retailer and hack the PIR unit. The
PIR piezo element needs a lot of amplification and there
should be a quad op amp inside the PIR unit that will have
points at which you can take off a usable signal

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