2006 I fiddled with some simple drawing routines in SuperCollider. (swiki.hfbk-hamburg.de:8888/MusicTechnology/833). Now I've added matching (?) sound synthesis and some slight modifications to the drawing code. There are 7 parameters that are used to both generate the picture and the sound. Normally the parameters are randomised but it is possible to copy&paste a good sounding/looking set of parameters into the code to get the same drawing back.
I bought the klinkenstecker 3.5mm 4pol for €2,40 from Segor. The capsule microphone I had laying around. Sorry, no data or idea where I got it. The whole thing is very simple to build and the sound is totally all right. Now I can record into the iPod Touch and run apps like RjDj and SuperCollider with audio input.
For our recent installation at ISCM World New Music Days in Växjö (www.musicalfieldsforever.com/interactive-art/searching-voices/), I built a circuit for controlling 9x5m el-wire (electroluminescence). There are 9 channels in total and 3 inverters that are powering three 5meter cables each. TIC201d TRIACs are used for switching the 110V AC on/off, 9 led+LDR pairs (aka Vactrol) generates the control voltage for the TRIACs and wireless control for the whole thing is obtained with an ATmega8 and a pair of Nordic transceivers. SuperCollider is generating control data.
Something I knew all along but tried to ignore: Many of my noisier synths sound like crap on modern (Intel) macintoshes and some even go all silent. The code below deliberately blows up a resonant hi-pass filter and is typical for how different the same code can sound on my Intel vs my PPC mac. Listen to the attached MP3 files. In a few years, all the PPC computers will be gone and we can't recreate the sounds.
update 090811: Thanks to Batuhan Bozkurt for putting me straight. It's not an Intel vs PPC issue but rather Apple changed something in their internal soundcards. Using a newer (Intel) machine and an external soundcard (Fireface 400), the punk code sounds the same as the PPC version below (i.e good/better in my ears - no autocompression).
So the internal soundcard in my old PowerBook (1GHz, PPC) is robust, filters hardly ever blow up and it doesn't have that automatic compressor/limiter as my newer MacBook Pro (2.16GHz Duo, Intel) internal soundcard.
update 180101: With GlitchRHPF from sc3-plugins and some clipping one can get the original sound back...
A cheap little circuit that reads 10 analogue controllers (8 knobs and 1 joystick). I built it for my neighbour Jens' portable keyboard project. It's using an ATmega88 and a 4051 multiplexer to get 10 analogue-to-digital converters. A standard MAX232 with some caps lets the ATmega88 talk to the serial port of the computer.
Attached is schematics, AVR firmware and a MaxMSP patch for testing.