Stan Lunetta's Moosack Machine (1970)

via this electro-music.com thread:

"Stanley Lunetta
Moosack Machine
March 7 - April 19, 1970

The moosack machine is a sculpture that produces, mixes and processes electronic sound. In the present version, the machine routes these sounds to four speakers placed in four corners of a room, and also to an audio transducer contained in the sculpture in the center of the room.

The moosack machine has two parts. The first, completely contained in the sculpture, consists of four variable oscilators, two power regulators, and a large number of input sensors. The input sensors detect changes in light, temperature, wind direction ands well as movements of people around the sculpture. These components are assembled as a sculpture, using the resistors, capacitors wires, etc. for their appearance as well as for their various electronic functions.

The second part of the moosack machine contains four mixers, the fixed oscillator/frequency divider unit, the relay box, the digital logic system, plus filters, phase shifters and reverb/tape-echo units.

The variable oscillators, controlled by the input sensors produce constantly changing output signals; e.g., continuously variable sweeps and/or disjunct leaps in either direction, amplitude, and time-event changes, and off/on functions. The output of each variable oscillator is mixed with one of the outputs from the fixed ocillator/frequency-divider unit and is sent to the digital logic system.

The digital logic system consists of a 16-bit digital counter/decoder, modified to have four inputs and eight outputs. Each output will function only when the inputs are in specific states. For example, output X1 will function only when the outputs of oscillators A, B and D are positive, and oscillator C is negative. Further, the four fixed oscillator/frequency-divider outputs (A,B,C,D) must also be positive-positive-negative-positive, if the output is to function. The fixed oscillator/frequency-divider unit moves from positive to negative at a very slow rate, changing its state one to three times per minute. Thus, the output of the digital unit consists of the relationships between variable and fixed oscillators.

Through the relay box, the four outputs of the digital unit have control over the on/off functions of the electric motors in the sculpture, turning the "cut-out wheels" and affecting the light-sensitive input sensors. There are also photo-cells that override the X outputs, turning off the relays.

The four Y outputs of the digital unit are used as audio outputs and are, of course, square waves. Thses outputs are either filtered, phase shifted, sent throuogh reverb/tape-echo units or frequency divided. The resulting sounds are then heard through the four amplifier/speaker channels. The fifth channel, a transducer in the sculpture itself, is taken from one of the mixers before the signal is sent to the digital logic system. Ideally. the moosack machine should be activated in the morning and allowed to play through the afternoon. The only human control over the moosack machine is the on/off switch. The recording in this issue was not edited or "composed" in any way. The moosack machine was allowed to play for 23 minutes. The record contains activities from the third to the eighteenth minute.

P. 46"