electronics

i have constructed a wireless sensor system for my performance costume. it has 2 accelerometers (3-axis adxl330, sparkfun - same as in the wii remote i believe) and 4 switches (digital). both master and slave uses a microcontroller (atmega8, atmel) and a transceiver (mirf v2, sparkfun).
below is a short video, some pictures, supercollider classes and also the schematics and the complete firmware if you want to build the thing yourself.

redUniform-hardwareWireless from redFrik on Vimeo.

the avr programmer (usbtinyisp kit v2.0) and the electronic parts needed...

the master and slave...

sensors sewn in...

081008 update: slave firmware and slave schematics updated - added 2 more switches (pd6 and pd7)
081010 update: also attached the supercollider class RedUniform.sc with helpfile

built six more little micro_noise2 synths. so simple yet so noisy and evil sounding.

trying to finish this custom controller before leaving for japan. almost ready now - just the casing left to do. it has 5 rotary encoders (endless) with as many push buttons, 2 softpots and 3 touch sensors (capacitive). it is built using the absolutely brilliant avr-usb from obdev and shows up like a standard HID devices. small, lightweight and just one cable (usb). plus it is very cheap to build - see parts list. the biggest cost is the encoders.

i took some inspiration for the design from kenton's nice but expensive killamix mini, but wanted a few different types of controllers and also have them arranged asymmetrically. this so i don't have to look at the device while playing. when i've tried other controllers with evenly spaced knobs, i've often lost track and have had to look down and even start counting knobs to figure out which one i was using. with this layout i won't have this problem. also the layout resembles the shape of my upcoming performance costume redUniform.

schematics, partslist and firmware attached (v1.0). a proper release is here.

this is my hacked front light for my bike. it's a tiny45 avr microcontroller that i programmed to play the complete 14min drum part in ravel's bolero. the reason i picked bolero was that it's a fairly well known rhythm and that it's very repetitive (= don't require much memory).
firmware attached.

bikelightBolero from redFrik on Vimeo.

i was so fed up with only listening to music in headphones, so with the help of my dad i built a pair of SQ-50L. they sound really great. full and rich sound. i have a sonic impact t-amp gen2 to drive them.

this is version 2 of a minimal and cheap one-bit synthesizer i developed for this workshop. basically i just changed the hardware and took out one of the potentiometers and lowered the oscillator to 1mhz. now it sounds a lot different and more chaotic.

monijonsyn2 from redFrik on Vimeo.

finally found some time to build a tiny synth based on a design by SGMK (mechatronicart.ch). so simple and it sounds so good! evil little thing. i did some modifications: basically one more audio channel with different pots and caps and 2 switches for the ldr.

micro_noise2 from redFrik on Vimeo.

as part of the xxxxx-workshops series at this year's club transmediale, i was asked to do a day on one bit music. this is a very silly way to produce music - basically flipping pins on/off with no amplitude control! but i liked the challenge and for me limitations like these are needed to get anything done at all. thanks to anke, martin and derek for organising.
attached are the slides, arduino code and schematics we used that day.

the workshop (6-hours short) was divided into 3 parts: first some theory about microcontrollers, avr programmers and coding in c. then we used arduino to prototype some simple synths (bit-bang and pwm techniques). and last we took the arduino code and burned it onto a standalone mega8l chip and built minimal circuits (some buttons, battery, chip, speaker).

if you want to try to do sound synthesis with the arduino, you might want to check out the files in 1bitmusic_arduino.zip below. this file also includes code for my little synth called monijonsyn.