David Tudor wrote about the development of Bandoneon! in what he called a “Pre- & post- operative note”

 

My first plan for the 9 Evenings was to have been a realization of my friend Mauricio Kagel’s Mobius strip composition Alle Rechte vorbehalten, using only white noise as a source, gated, triggered, etc. in a complex fashion by some instrument. The idea abandoned itself thru the process of my projecting my thoughts into the about-to-become available technology and its potential for the creation of ‘white noise’ from scratch.

 

The technology he was referring to was the overall  wireless communication system that a group of the engineers was developing, —“with strong input from Tudor,” Billy Klüver recalled much later in 1996—and was named “Theatre Electronic Environmental Modular System,” or TEEM for short. Tudor remembers working on the system:

 

We had to work on the audio systems and the programming of the audio systems. And I had a large part in the basic design parameters, so we decided how to go for clean audio, whether to make it portable... I was working at the electronic end of it, and I noticed that the whole system had been created because each artist wanted certain things to happen but they require different components. Well, I noticed that nobody was really using a lot of the features of the system, so I said, I’ll put everything into this.

[“Presenting Tudor: A Conversation with Bruce Duffie,” April 7, 1986 http://www.bruceduffie.com/tudor3.html ]

 

In Bandoneon! David Tudor played the bandoneon, whose sounds were processed and modified by modular electronic equipment  --  audio  processing and modifying units designed and built by Tudor, a frequency-sensitive Vochrome and a program switching unit by Robert Kieronski and the proportional control system by Fred Waldhauer  -- and then switched between speakers and acoustical modulators placed around the Armory.  The sounds from the bandoneon also controlled theater lights and created television images.  Tudor titled his work Bandoneon! (Factorial): a combine, which uses a name that Bob Rauschenberg had given to describe his works of the 1950s that incorporated  painting, collage, objects and constructions in one work; and Tudor, too, in this work combined  elements of live performance, sound, light, and movement.

 

When the performance started, Tudor was sitting on a 16 x 24 foot platform on the floor of the Armory in front of the control booth, on which all the electronic equipment for the concert was placed.  He played the bandoneon, and eight contact microphones attached to the bandoneon  and 2 air mikes picked up the sounds which were then distributed to different processing devices: to an audio processing unit, consisting of modulators, tone sources, filters and frequency shifters, to a set of frequency-sensitive relays of the Vochrome and to the Proportional Control System. 

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The 18 channels of signals from the audio processing unit were switched by a 12-pole, double-throw relay, which was controlled by signals from the frequency-sensitive relays in the Vochrome, and by 6 channels on the proportional control unit, then went through the Program switching control unit built by Kieronski; and were distributed over the 12 speakers mounted in the balcony around the Armory. Output from Tudor's modification unit went directly to FM transmitters that sent the sound to the horn speaker, and  to the acoustical modulators or drivers attached to 4 constructions of wood, metal and glass, which became additional speakers on the floor of the Armory.  These constructions and the horn speaker were placed on the remote controlled platforms, that had been designed for Deborah Hay's work, and moved about the floor of the Armory during the performance.

 

The 1-Kilowatt lights mounted on the balcony surrounding the space were turned off and on by signals coming directly from the frequency-sensitive relays of the Vochrome.

 

Waldhauer operated his Proportional Control System, a translucent board divided into 16 squares, under each was a light-sensitive photo-resistor. When Waldhauer shined light from a pen-light on one of the squares, the electrical resistance of the resistor under that square changed in proportion to the amount of illumination from the pen. This changing electrical resistance was used in eight channels of the proportional control system to control the brightness and rate of change of the 8 lights mounted on the performance platform. The remaining channels from the proportional control system fed sound into the 12 speakers mounted on the balcony around the armory.

 

Using signals directly from the bandoneon, engineer Lowell Cross planned to use audio power amplifiers to drive the deflection systems of the three projection television systems, each one different, and have the resulting images projected onto large screens. This use of the video projectors was not technically possible, so during the performance his image control system activated and oscilloscope, and the images it produced were fed to the video projectors on the floor of the armory, and appeared on large white screens.

 

Tudor made full use of the six-second reverberation time in the Armory.  At certain points, he stopped the sound from all speaker sources and waited a few seconds for the existing sounds to reverberate through the space, and then reactivated the Armory with a new sound from the bandoneon.  When Tudor played the bandoneon, he, in fact, played the whole Armory environment with sound and light.

 

NOTE: For a full description of the technology of Bandoneon! see

You Nakai, Reminded by the Instruments: David Tudor’s Music,  Oxford Press, 2021, Chapter 4, pps. 215 - 265