HPSCHD

The 1969 LP release of HPSCHD was more than a recording of a landmark piece of experimental music. It came with instructions on how listeners could treat their home hi-fi as an instrument to create a unique interactive experience.

John Cage and Lejaren Hiller composed the work during a residency at the University of Illinois using the Illiac II supercomputer, which not only generated the score but also produced the electronic sounds incorporated into the piece. (The title shortens “harpsichord” to meet Illiac II’s six-character limit for file names.)

Cage’s chance-based methods left decisions about duration, entrances, and ensemble size to the performers. it specifies an instrumentation of “one to seven amplified harpsichords and tapes for one to fifty-one monaural machines.” HPSCHD united an early-modern instrument with cutting-edge technology, while also linking Cage’s methods to a classical precedent. The score reuses some figures from “Introduction to the Composition of Waltzes by means of Dice,” a 1787 score attributed to Mozart that instructed players to select measures from eleven options with dice rolls.

The Nonesuch LP embodies Cage and Hiller’s ideas in a vinyl LP. Each copy included KNOBS, a print with instructions on how to adjust a stereo system’s volume, treble, and bass every five seconds to reshape the music in real time, since some solos appeared only in certain channels or frequency ranges. The instructions were randomized, so that each listener would have a unique experience when following them. In this way, the HPSCHD LP turns passive home listening into a participatory, always changing event.