DATA-log

2nd episode focuses on the innovative photo-electronic ANS synthesizer.

Unidentified Flying Oscillator #2 (24.9.2010) tracklist:
Oleg Buloshkin – Sacrament
Artemiev & Kreitchi – Music from cosmos
Sofia Gubaidulina – Vivente
Coil – untitled (from the Coil ANS cd)

Episode MP3:
http://www.radiofreerobotron.net/ufo/unidentified_flying_oscillator_2.mp3

Radio Free Robotron, my experimental internet radio setup, is back online running in a dedicated machine 24/7. The system is serving requests in the ircnet channel #rfr via an ircbot.

http://www.punainen.org/~biotek/radio_free_robotron

The radio system currently supports some interactivity in the form of synthesized speech shoutout and request functionality. More could be done with it however. Current future plans include webcrawling information and music file extraction and also some form of soundcloud integration where the system analyzes the music tags and processes the music into a radio stream.

I think the internet can offer new insights into this old aging medium, in the form of commune driven interactivity and automatic computational analysis.

To complement the FPU post below, here’s a similar approach to the well known Lorenz model used in chaos studies. There’s an increasing Rayleigh number used in the computation of this clip.

Lorenz0001 by janne808

It’s obvious that there are very interesting regions of nonchaotic behaviour in the model.

Current studies have led me to meddle with the famous FPU (Fermi-Pasta-Ulam) problem. Unsuprising event, since it is one of the cornerstones of the study of computational physics.

It was one of the first problems that was tackled not using analytic math tools, but using high speed digital computing. The reason behind this sort of approach was the difficulty of dealing with nonlinear equations; something that is near impossible to deal with exact analytical attacks. Digital computers and numerical analysis however is the ideal tool to conduct these sort of chaotic computational experiments with.

A lot has been written about the FPU problem (try the wikipedia article for a decent summary), but an immediate way to grasp the problem is by hearing how it sounds. The system described in the problem consists of masses coupled together, the usual scalar wave equation with nonlinear coupling terms added. Here the initial gaussian pulse oscillates in the system without damping and with increasing nonlinearity.

Fpu1 by janne808

Another example is done with a custom VST plugin. The system is driven with two pulse oscillators.

Fpu2 by janne808

I’ve been kept busy by Schrödinger, Fourier and Dirac lately, but I had some free time finally and put together a more refined way to derive musical (or so) structures out of one dimensional cellular automata system. Partly inspired by the excelent lectures on early finnish experimental electronic music scene at the local media art museum (see http://mansedanse.com/events_fi.html).

The algorithm quantizes the chromatic scale down to any arbitrary scale and picks up two notes to be played. This produces a more music-like result than the total chaos of applying the whole automata state straight to the chromatic scale.. though I’m not saying that it can’t produce interesting results.

http://www.punainen.org/~biotek/cell0011.mp3

http://www.punainen.org/~biotek/cell0012.mp3

Here is the MATLAB code responsible for these, keep in mind though that the quantizer code was written in the middle of the night (I think you can tell) so there are probably some glitches to it.

http://www.punainen.org/~biotek/automata1.m

What would be better application for one dimensional cellular automata than autogenerative electronic music. I know Wolfram Tones offers something along these lines but I set out to experiment on my own first with just the bare rules applied to the chromatic scale. Couple of important rules rendered on the chromatic scale:

http://www.punainen.org/~biotek/rule30.mp3

http://www.punainen.org/~biotek/rule110.mp3

These does seem to hold a eerie quality to them, not that anyone would recognize them as music. Next I cherrypicked a good set of rules which seemed to work nice enough when applied in a random order. I think I used the c major scale for this one.

http://www.students.tut.fi/~heikkara/autobach4002.mp3

That sounds a lot more like music, almost emotional at times. This is a Processing program playing midi notes to a Roland Jx-3p.

Since googling up NASA’s online VLF receiver mp3 stream (seems to be defunct now, fortunately there are other streams available.. see http://abelian.org/vlf/) I wanted to try to receive these signals myself. So I came up with some schematics on the internet for a basic vlf receiver and built and tested a couple of these.

E-field receiver clip 1

E-field receiver clip 2

The sferics are crisp, loud and clear, the circuits work very well if the conditions are right. Small enough to fit a pocket, it’s interesting to walk aroud the area I live and listen in to the various weird signals eminating from all sorts of electronics and machinery. I’ve yet to record auroral activity, but that is next on the agenda.

I thought I’d share a few interesting internet radio streams here on my blog.

Live underwater antarctic stream

NASA online VLF receiver

NASA online 67.25MHz MSFC meteor radar

Interestingly the sounds you can hear thru these aren’t really that different, although the phenomena involved are totally different to each other.

I got around programming some perl and php hacks to interface a web page with the liquidsoap server running the radio. Enjoy.

http://www.punainen.org/~biotek/radio_free_robotron/request.php