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Collaboration with Jochen Gerz, Paris







LESER 1, is a "visual poetry" interactive kinetic / sound machine, 1966-67

Text: Jochen Gerz, Audio Sculpture: Manfred Mohr
Polyester tube / 19 loudspeakers / printed transparent plastic bag / 19 moving ping pong balls,
electric motor, 180cm x 45cm, 1967

Manfred Mohr designed and constructed the electrical mechanics, the sound, and the sculpture: The sculpture is partitioned into 3 interlocking plastic tubes - top, middle, bottom. Each part contains a certain number of loudspeakers. In front of each loudspeaker membrane a ping pong ball, with a random letter printed on it, is suspended. The transparent plastic bag, with the text by Jochen Gerz printed on it, fits over the object when the three parts are stacked together. When the foot pedal is pressed, the loudspeakers in the 3 parts vibrate at different frequencies, thus hitting the ping pong balls with different forces. Sound is thus created when each ping pong ball hits the plastic tubing, each section having a different speed. The vibrations continue for around a minute, thus creating a "symphony" of noise.

This sculpture was shown at the one-person exhibitions of Manfred Mohr at Galerie Daniel Templon Paris 1968 and Galerie Anne-Marie Verna Zurich 1969 and in a group show at the Musée d'Art Moderne de la Ville de Paris in 1967 or 1968.




Page from magazine Agentzia Numbero Double 11/12, 1969



Le system binaire dans la peinture de Manfred Mohr Wolfgang Sauré, 4 Soli, Torino, April 6, 1969



Dr. Cathy van Eck, Between Air and Electricity: Microphones and Loudspeakers as Musical Instruments:
Other examples - Fifty years of loudspeakers and ping pong balls, webpage of book, Bloomsbury publisher, February 2017




Jochen Gerz webpage about Leser 1
Image courtesy Jochen Gerz website













Physik-Lehrer plant...
Text: Jochen Gerz, Drawing: Manfred Mohr
Ink on paper, 29.7cm x 21cm, 1967









1+1, Jochen Gerz + Manfred Mohr, Montréal Edition Gheerbrant, 1972
Image courtesy Jochen Gerz website