adventures in circuit bending, diy electronics and experimental music
This is my hardwire mod of the Dirty Carter Experimental Sound Generating Instrument, a post card sized hand held touch controlled instrument, designed by John Richards (Dirty Electronics) and Chris Carter ( Throbbing Gristle, Carter Tutti). It was originally produced for a special performance by Carter and the 25 strong Dirty Electronics Ensemble in 2010. Chris’ artwork is etched into the PCB and forms part of the circuit.
The instrument is mounted on a custom built wooden case with aluminium face plate covered with black leatherette.
On this mod all the touch points are wired up to pots, with rotary switches to select clock range and feedback input, giving more precise control and predictability. The mix tilt switch is disabled and rerouted to a toggle switch. The original speaker is removed and a ¼ audio out socket added. Also added is a low pass filter with resonance and cutoff controls and LFO for modulation and CV in. At full resonance the filter self oscillates.
The original instrument and additional circuitry are powered from a 9v PP3 battery.
The Instrument uses a dual 4-stage shift register. Each register is controlled independently. Two oscillators are used per register: one as a clock, the other as input data that is cascaded through the four stages. The outputs from the stages are mixed together. A fast clock rate produces a crude form of wavetable synthesis, whilst a slow clock rate creates audible pulses and clicks. The clock speed and the data input’s frequency are controlled by touch electrodes/pads. By tilting the instrument, sound from both the 4-stage shift registers can be mixed together. Glitchy noise, deep drones and percussive peeps!