Chapter 13. Meeting 13, Interfaces: Modular Synthesizers13.1. Announcements• Quiz on Thursday • Music Technology Case Study Drafts due next Tuesday Draft should meet minimum requirements of final paper Contact me with questions or problems • Today: we will look at modular synthesizers in part through Arturia’s virtual instrument emulations. Next Tuesday we will build similar models in PD. 13.2. The Modular Synthesizer: Overview• The Modular Synthesizer: a collection of voltage-producing components with inputs and outputs freely inter-connected with patch cables • Semi-modular synthesizers: voltage producing components with a mixture of fixed, switchable, and/or selectable interconnections • While composers such as Varèse and Stockhausen were synthesizing tones in the 1950s, the synthesizer was not a conceived of as a single hardware entity • The modular synthesizer was, in part, a consolidation and repackaging of existing technologies • Voltage control, the flexible automation of parameters, was a (the?) key innovation 13.3. Foundations: RCA Synthesizer• RCA Synthesizer 279Courtesy of Kevin Lightner. Used with permission. • 1940s-1950s: Harry Olsen and Herbert Belar, working for RCA, explore music machines with vacuum tube and tuning fork oscillators • 1955: complete Mark I, features 2 voices Sine tooth signal from tuning forks converted to square and then sawtooth waveforms (1955, p. 599) A variety of AR envelopes possible with “growth and decay” generators (1955, p. 602) Timbre control with high and low pass filters with variable cutoff frequencies and a “resonator chain” (1955, p. 605) • Olson, H. F. and H. Belar. 1955. “Electronic Music Synthesizer.” Journal of the Acoustical Society of America 27(3): 595-612.Perhaps the first description of an instrument as a “synthesizer” Two channel, fixed signal flow, controlled by punched paper 280© Acoustical Society of America. All rights reserved. This content is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse.Electromagnetically driven tuning fork oscillators © Acoustical Society of America. All rights reserved. This content is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse.3 and 4 bit binary parameter specifications 281© Acoustical Society of America. All rights reserved. This content is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse.Direct to disk output recording 282© Acoustical Society of America. All rights reserved. This content is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse.• A first attempt at a rigorous, fixed, and complete parameterization of musical events • Not a performance instrument 13.4. Foundations: RCA Synthesizer Mark II• 1957-1959: Columbia University, with Rockefeller Foundation grants, purchases the RCA Synthesizer Mark II and establishes the Columbia-Princeton Electronic Music Centre. • Mark II features four voices similar to the Mark I, adds a white-noise generator, microphone input, and variable frequency oscillators • Olson, H. F. and H. Belar, J. Timmens. 1960. “Electronic music synthesis: the Mark II R.C.A. Synthesizer.” Journal of the Acoustical Society of America 32(3): 311-319.• RCA Synthesizer disk cutting lathe 283© source unknown. All rights reserved. This content is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse. • Eventually installed three-track Ampex tape recorders • Audio: 1955 Demo recording demonstrates dance band synthesis 13.5. Listening: Babbit• Audio: Milton Babbitt, Philomel, 1964 284• 12-tone technique applied to pitch and other synthesis parameters • What is the role of the electronics in the context of the piece? 13.6. Foundations: Buchla• 1963: 100 Series Modular Electronic Music System 285Courtesy of Buchla and Associates. Used with permission. • 1965: Buchla releases Buchla Box, without a keyboard • 1970: 200 Series Electric Music Box 286Courtesy of Buchla and Associates. Used with permission. • 1971: 500 Series: First digitally controlled analog synthesizer • 1972: Music Easel 287Courtesy of Buchla and Associates. Used with permission. • 2002: Buchla 200e (19k+) 288Courtesy of Buchla and Associates. Used with permission. 13.7. Foundations: Moog• 1954: Moog publishes article in Radio and Television News on how to build a Theremin 289© Radio and Television News, 1954. All rights reserved. This content is excluded from our Creative Commons license. For more information, see http://ocw.mit.edu/fairuse.• 1961: Moog publishes article in Electronics World describing his transistor-based Theremin • 1964: Moog, with composer Deutsch, builds first synthesizer prototype • 1965: Moog releases 900 series for commercial sales Synthesizers used by composers, for advertising, jingles, and in recording studios • 1966: Moog patents the 904A low/high-pass voltage-controlled filter with 24 dB / octave rolloff and resonance up to self-oscillation290291• 1967: Moog releases modular systems I, II, and III Courtesy of Roger Luther (http://www.moogarchives.com). Used with permission. 292Courtesy of Roger Luther (http://www.moogarchives.com). Used with permission. 293Courtesy of Roger Luther (http://www.moogarchives.com). Used with permission. • 1968: Wendy Carlos records Switched on Bach 29413.8. Concepts: Generators and Modifiers• Modules are individual signal generating/processing components • Two basic types of components: generators and modifiers • Input is from front-panel knobs or voltages • Output is a voltage 13.9. Concepts: Control and Audio Signals• Two types of signals (voltages): audio and control signals • Audio signals: • Sounds, alternating (bipolar) voltages in the audio range (faster than 20 to 30 Hz) • Voltage range from -3 to 3 volts (or wider) • Control signals • Parameter values, (unipolar) voltages • Voltage range from 0 to 5 volts (or up to 15 volts) • Used to send control information to other modules • Used to provide envelope shapes 13.10. Concepts: Reuse and Interoperability• Can use output of one module as a signal (audio or control) input to another • Can use an audio signal (shifted or scaled) as a control signal 13.11. Concepts: Creative Patching• Developing new signal