Thanks for sharing the video - this is great. I appreciated the questions you raised, Amanda, and thought I'd add a few. Since improvised music often depends on a group dynamic, I wonder if livecoding has any such equivalent. Do multiple livecoders ever perform together, responding to each other's changes? Or is the point that the code allows a single performer to be multiple? (I.e., the coder makes a change to one part and can respond accordingly in other parts.)

I also wonder to what extent we can reverse the analogy. In other words, having seen how livecoding suggests what we typically associate with improvised music, can we imagine a way in which a music performance suggests livecoding? What makes livecoding different, and can a traditional music performance mimic it? To answer this question, it seems important to note the ways in which improvised music often appeals to some notion of authenticity or genius. While livecoding might lend itself to some notion of coding virtuosity, "authenticity" seems out of place here. If improvised music is expression, livecoding suggests a setting of constraints on expression, describing the parameters through which the machine (midi) gets expressed.

I don't feel that I've answered the question with any certainty, but hopefully it is at least a productive one. Here are a few possibilities for music that perhaps mimics to some extent the principles behind livecoding. In Radiohead's performance of "Everything In Its Right Place," Johnny Greenwood and Ed O'Brien play Thom Yorke's voice, changing it from an instrument of self-expression to raw data expressed algorithmically (this is in some ways what _Kid A_ is all about): youtube.com/watch?v=fSpJEuNZxIk

In Battles's "Atlas," we can easily imagine the music (performed on "real" instruments) as code. Beats and instrumental and vocal lines are performed in such a way as to suggest a few components repeated and modulated: youtube.com/watch?v=IpGp-22t0lU

great movie, thanks!

on the improvisational character of this music.. well I think that there's a difference between improvising and playing randomly. Improvising requires a great deal of expertise, playing randomly doesn't. A bluegrass picker may not know how to read scores but he's surely an expert with his hands... and that lets him translate seamlessly his thoughts and emotions into music. In general, it is only by mastering an instrument that you can forget about the technique and concentrate on 'saying' things with the instrument.

So the amazing thing for me is Andrew's mastery of the 'random', 'cosr, 'sinr' etc. mathematical functions, the way he knows how to fine-tune them so to say what he wants to say ..
... in this sense I believe that the thought 'this note gotta be changed' did go through his head...

cosr might be the real portion of a cosine that's represented internally as a complex exponential? or in z domain?

edit -- maybe not, i'm only halfway through ;)

Fun! I remember having fun programming math music in QBasic to run the piezo speaker back in '93 on a 286. A private cave painting of Lascaux to this public Guernica.

Dang. Now I have to learn lisp.

sinr and cosr are almost certainly the radian version of sine and cosine functions.

Bangsplat, my thoughts exactly re. learning lisp.

excellent introduction to livecoding — thank you, stephen!

fascinating :) dare i ask, is there a win equivalent of impromptu?

the sort of 'feedback' synth sounded amazingly lush and organic

Great movie and how much fun to hear somebody else's interpretation of Sorensens work. I have limited knowledge in programming languages but as an electronic composer I am pretty certain about the cosr command. When Sorensen uses cosr he will input three values. It fascinates me how programmers refer to mathematic values but the electronic musician refers to synthesizer controller messages. cosr values is simply cutoff, sustain and release. If you look at the numbers this makes sense. I'm deeply impressed of what he does but I would personally prefer to call this live sequencing, since all dsp is going on where we can't see it. Still very impressive and inspiring.

amazing... i really enjoyed and learned from it a lot , thank your prof. ^-^