Rainforest IV (1973) is an electroacoustic environment conceived by David Tudor and realized at "The Art of David Tudor" symposium by the group Composers Inside Electronics. It grew out of a 1973 workshop in Chocorua, New Hampshire, that included David Tudor, John Driscoll, Phil Edelstein, Linda Fisher, Ralph Jones, Martin Kalve, David Tudor, and Bill Viola. In this performed installation, each composer designs and constructs up to five sculptures, which function as instrumental loudspeakers under his or her control, and each independently produces sound material to display the sculptures' resonant characteristics. The appreciation of Rainforest IV depends upon individual exploration, and the audience was invited to move freely among the sculptures. This excerpt takes the listener inside a hanging sculpture that appears to be a milk bottle, to reveal the transducer within.

In David Tudor's words: "Instruments, sculpturally constructed from resonant physical materials, are suspended in free space; each instrument is set into sonic vibration through the use of electromagnetic transducers . . . The sound materials used to program the instruments are collected from natural scientific sources and are specific to each instrument, exciting their unique resonant characteristics. The excited resonances are routed to a conventional audio system by the use of one or more pick-ups attached to each instrument." (Original program note, David Tudor papers)

Rainforest IV has been installed in thirty sites throughout the United States and Europe, including museums, universities, and television studios. This performance was realized through the collaboration of two groups of performers: Composers Inside Electronics (John Driscoll, John D. S. Adams, Paul DeMarinis, Ralph Jones, Ron Kuivila, Matt Rogalsky, and Bill Viola) and a collective of composers and performers from CalArts, directed by Mark Trayle.