The following pieces were recorded as part of my research project Taming The Ghost In The Machine which explored the history and practice of electronic feedback as a compositional technique.
The fundamental principle of electronic feedback involves routing the output of electronic devices back to their input which will create complex oscillations defined by the characteristics of the circuitry within the feedback loop. In other words, there are no external sound sources, only the sounds emanating from the feedback loop.
Composer and performer David Tudor produced electronic feedback works throughout his career, however he is likely best known for his piece 'Untitled'. Tudor would create large feedback networks by connecting chains of electronic devices such as amplifiers, phase shifters, filters, and modulators, and feeding them back to their inputs. These devices are traditionally used to modify a sound, yet when arrange in a feedback loop, produce complex oscillations and sonically unique events.
While researching Tudor’s feedback works, original schematics were uncovered for specific devices used in Untitled and other feedback pieces. These schematics were prototyped and then modified to add more control and options to the circuitry. The original Tudor circuitry built for this project, along with various other circuitry of original design, was constructed using some original components previously owned by Tudor, supplied by Dr. Matt Rogalsky.
The collection of prototyped circuits designed and built for the realization of 'Untitled' were integrated and mounted onto a metal face plate, facilitating the interconnection of circuits through patch cables. The collection of fifteen circuits includes: High and Low-Pass filters; Diode Ring Modulators; Four-Quadrant Multiplier, Variable Frequency Divider, Voltage Controlled Amplifiers; and, Amplitude Modulators.
The original score for Untitled was used as a guideline to configure device interconnections and signal paths for the feedback network. A series of five improvisations were recorded, each with different device configurations.
Star Networks at the Singing Point is a live, group performance created by composer Ralph Jones (1978). Feedback is generated by connecting an amplifier’s input and output through passive electrical components configured in a star network, which is described as having three or more components connected at a single node. By increasing the gain of the amplifier, the sound, “changes intermittently and unpredictably such that the circuit begins ‘singing’ of its own accord," (Jones). These sounds are unstable, randomly jumping across paths in the star network, and can sound like crickets, balloons rubbing against each other or jackhammers, for example.
During a performance, musicians independently create ‘singing’ sounds and then release them to the audience, adding to the density of chaotic sounds created by the other performers. This process is staggered and repeated amongst performers such that more than one networks are ‘singing’ at any given time.
Two performances were recorded on June 6th at the Isabel Bader Centre of Performing Arts by performers: Dr. Matt Rogalsky, Dr. Roel Vertegaal, Jeremy Kerr, Dimitri Georgaras