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LMJ13_02body_005-096 11/25/03 2:57 PM Page 39 Regenerative Feedback in the Medium of Radio: Study 1.0 (FM) for Radio Transceiver Matthew Burtner ABSTRACT The author discusses he Studies for Radio Transceiver (2001), pre- lowing the production of an inde- compositional applications of T feedback in the medium of radio sented here, join a tradition of creatively repurposing audio pendent oscillation, a process he as a means of exploring the tools in order to explore the nature of media. A rich body of called “regeneration” [1]. Arm- nature of transmission and compositions using radio signals has been created, including strong’s circuit describes regenera- reception. His Studies for Radio John Cage’s Imaginary Landscape No. 4 (1951) for 12 radio re- tion of the electromagnetic waves, Transceiver are presented here along with a detailed discussion ceivers; Karlheinz Stockhausen’s Hymnen (1965–1967) and or “feedback,” as a means of ampli- of Study 1.0 (FM). This composi- Kurzwellen (1967), which used shortwave radio signals; and on- fying the signal until it creates its tion juxtaposes the historical going projects by musicians such as Holger Czukay and Robin own continuously oscillating elec- and technical use of feedback in Rimbaud (a.k.a. Scanner). These works notably concentrate tromagnetic signal. Figure 1 shows radio with audio signal recur- on the reception of existing radio signals, focusing on col- a photograph of the inside of an sion. Regenerative feedback is used to redefine the composi- lecting preexisting transmissions and in many cases juxtapos- Armstrong regenerative super- tional capabilities of the ing and layering simultaneous unrelated and randomly heterodyne receiver of 1917 [2]. medium. occurring signals. In 1933 Armstrong made an- The Studies for Radio Transceiver expand on this work by ex- other contribution to the technol- amining the nature of radio transmission itself, the music ogy of radio, creating the first being a byproduct of both the transmission and reception of working demonstration of FM. The FM transceiver increased an audio signal. In particular, the first in the series, Study 1.0 the dynamic stability (and therefore the range) of the trans- (FM), considers the broadcast and reception of an FM radio mitted signal by modulating its frequency rather than its am- system’s self-noise; regenerative feedback is used here to re- plitude. Armstrong began making regular FM broadcasts from define the compositional capabilities of the technology. the top of the Empire State Building until he was forced to move out of New York City [3]. By redefining a transmission medium as an instrument, the TRANSMISSION/REGENERATION composer may seek expression as the actualization of the The notion of information transmission is critical in the canon medium itself. A medium such as radio, meant to capture and of 20th-century audio technologies. As an undergraduate at repeat human expression, brings with it the implication that Columbia University, Edwin Armstrong studied Lee De For- a message is contained in the signal. However, despite the fun- est’s radio tubes, which had been designed for the Marconi damental connection of radio transmission technology to feed- radio company. He altered the De Forest tube by feeding high back, this presumptively transmitted content is subverted if levels of electromagnetic waves back through the tube and al- the signal is recursively fed back into the system. Signal re- generation allows the nature of the medium to take on pri- mary importance, asserting itself into the audio content of the Fig. 1. Inside view of the Edwin Armstrong Superheterodyne Re- message. Thus, feedback points to the conception of the ceiver of 1917. Armstrong’s modifications of Lee De Forest’s tube are the basis for the technology used to compose the Studies for medium as an instrument, the process of signal generation be- Radio Transceiver. The three-element tube allowed for the amplifica- coming the signal itself. tion of signals and production of radio signals. (Photo © Matthew Burtner) THE STUDIES FOR RADIO TRANSCEIVER Study 1.0 (FM) is the first in a larger series of Studies for Radio Transceiver, part of the World Noise Radio Project (WNRP). This project questions the nature of the radio medium in general and particularly the role it plays in forming the content of a musical signal. It explores the alteration of sonic content as it is passed through a medium to a receiver. The project was first defined in a lecture on the question of content and medium presented as a remote FM transmission to Brian Ferneyhough’s composition seminar at Stanford Uni- Matthew Burtner (composer, educator), Composition and Computer Music, Virginia Center for Computer Music, McIntire Department of Music, University of Virginia, Charlottesville, VA 22903, U.S.A. E-mail: Ͻ[email protected]Ͼ. © 2003 ISAST LEONARDO MUSIC JOURNAL, Vol. 13, pp. 39–42, 2003 39 Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/096112104322750764 by guest on 29 September 2021 LMJ13_02body_005-096 11/25/03 2:57 PM Page 40 versity [4]. In the conceptual art piece, points on a frequency spectrum become consequently polluted with powerful sig- WNRP, the medium of radio itself pro- ideological bridges over which we pass nal transmissions. Collecting unpolluted vides musical content. Accordingly, com- into an unoccupied, peaceful world. radio signals became increasingly prob- In remote parts of the North, scan- lematic with WNRP. Therefore a new In- positional content before transmission is ning the FM dial reveals that no human ternet radio station was formed that only minimized in order to focus on the prop- signals are being broadcast. The feeling broadcasts noise. Internet radio, unlike erties of the medium through broadcast provoked is one of aloneness, isolation, its analog, wireless companion, is suspi- and reception. and vast spaces. By contrast, scanning ciously lacking in random noise. Degra- the FM dial in populated parts of the dation of quality is introduced as a The Studies for Radio Transceiver are best world creates a feeling of acoustic claus- byproduct of file encoding, but the described by the score itself, which is a trophobia. This piece attempts to use the medium lacks the inherent chaotic series of text instructions for realizing the real time noise net as a means of recon- acoustic properties that characterize the pieces. The performable pieces of the structing a world of emptiness. signal of analog radio. A version of the group were first presented on 4 October Study 1.2b (net). Once the net is estab- Internet World Noise Radio Project was lished, the radio transmitter transmits a first broadcast (since September 2001) 2001 as part of the Strictly Ballroom series’ silent signal, and the performer freely al- at Ͻhttp://www.live365.com/stations/ “Mechanical Music” concert at CCRMA, ters the circuitry and broadcast fre- 278291Ͼ. Stanford University. Each study exploits quency. The frequency modulation takes a particular aspect of transmission and over each receiver in a different way, and a variety of radio sounds can be pro- STUDY 1.0 (FM) reception through the FM medium. duced by altering the capacitance and FOR RADIO TRANSCEIVER Studies for Radio Transceiver antenna length of the transmitter, and by Matthew Burtner, 2001 moving around the concert space. The Study 1.0 (FM) for Radio Transceiver refers These pieces can be performed in any “net” is heard as coming to life, each to Armstrong’s work and the origins of order, manner. node evolving into a voice of its own, gen- frequency modulation by using feedback Study 1.0 (FM). Transmit a silent sig- erating a polyphony of radio noises. to amplify the signal properties of FM nal. Receive the signal and feed the line Study 1.3 (drift). Broadcast some rec- outputs of the receiver back into the ognizable music over the FM transmitter. and of a specific transmission/reception transmitter. A loop is created in which As the audience listens to the transmis- circuit. The characteristics of the the listener hears the compounding of sion, the transmitter is gradually moved medium are revealed in the noise-to- the inherent noise generated in the pro- away from the receiver. The music at first pitch transformation brought about by cess of transference. The growth of the is clear but gradually becomes noisier. systemic noise moves from the periphery On the fishing boats in Alaska, as the the feedback system. of the music, a byproduct of the media, boat moved into a storm or down the Study 1.0 (FM) uses gain control of the to the central focus of the musical mate- coast, away from the transmitter, the sig- feedback into the circuit as a means of rial. We hear the resonance of the FM nal would gradually disappear. I re- slowly revealing the properties of the sys- band grow from noise, the intoning of member sitting close to the speaker, tem. A radio transmitter transmits an the medium. trying to catch the fading notes of a piece Study 1.1 (diffusion). Transmit a musi- of music as it vanished without a trace cal signal in a concert setting. The au- into noise. Poor audio reception creates dience provides the sound system for the a sense of intimacy, like watching the last Fig. 2. Electronics setup for Study 1.0 (FM) concert by tuning in on a variety of re- flames recede into embers in the fire- showing the signal path. (© Matthew Burt- ceivers to the specified frequency. The place. The impoverished quality and sub- ner) number, quality, and spatial positioning versive noises on old records create a of the speakers create the sounding re- feeling of nostalgia. Similarly, any fa- sult, a result that, although fixed in trans- miliar medium that once served as a con- mission, will be diffused differently for duit for artistic perception evokes a sense each performance.