[sdiy] Tape head collage (pretty much not synth DIY, sorry)

[Ian Fritz]

At 06:31 PM 11/19/2004, Tom Arnold wrote:

>Not that I want to see the thread start up again, but arnt those just
>pictures of lissajous figures?

They are more than that.  They are plots of x vs. dx/dt or d2x/dt2 for a 
non-linear dynamic system.  In other words, 2-dimensional projections of a 
3-dimensional phase-space orbit.

>If so, arnt they just a different way of
>viewing standard waveforms and not some weird "circular/spiral" waveform?

You are looking at it backwards.  The standard waveforms are the 
1-dimensional projections (vs time) of the circular/spiral/chaotic/etc 
phase space orbits.

>The biggest problem I had with the whole circular waveform thread was that
>you see on a scope is a visual representation of a frequency, for us, of
>sound, which has no bearing on the "sound" at all and in fact is fairly
>arbitrary.  The closest thing in my mind to a circular waveform would be
>the output of a sheppard generator, which wouldnt "look" circular at all but
>sounds circular.

No, a circular orbit corresponds to sine and cosine signals.  A Sheppard 
generator is more like a helical orbit on a torus.

>Also, reality check... do we care what a waveform "looks" like?  I mean, the
>point of a synth is the sound right?

Didn't you like my sound clips? <pout>

>Oh god, what have I done.

Good questions and discussion.  The geometric view of dynamics takes some 
getting used to.

   Ian