| Subtitle: | Electronic Music of TUESDAY from LIGHT |
| Composer: | Karlheinz Stockhausen |
| Translation: | Octophony |
| Catalogue: | 255 |
| Opus: | 1. ex 61 |
| Year: | 1991 |
| Genre: | Electronic music |
| Related: | Dienstag aus Licht Invasion mit Explosion |
| Publisher: | Stockhausen-Verlag |
| Scoring: | 8-track tape |
| Vocal: | Soprano, bass |
| Instrumental: | Synthesizer |
| Premiere Date: | 1994 |
| Premiere Location: | Cologne Triennial |
(Octophony) is a 1991 octophonic electronic-music composition by Karlheinz Stockhausen. A component layer of act 2 of the opera, it may also be performed as an independent composition. It has a duration of 69 minutes.
Oktophonie is the accompaniment for the onstage action in Act 2 of Dienstag aus Licht. During "Invasion—Explosion mit Abschied" (Invasion—Explosion with Farewell), the musicians synchronize their performances to the pre-recorded tape of Oktophonie. In order to balance their live performances with the taped synthesizers, all of the performers wear wireless microphones. This became a standard performance practice for Stockhausen after Dienstag.
Like everything in Licht, the music of Oktophonie is developed from Stockhausen's superformula. The music has eight layers which move independently. Because Act 2 of Dienstag depicts a battle between Michael and Lucifer, the music of Oktophonie evokes the sounds of battle. Much of the synthesizer material is dominated by drones. The more frenetic sounds on the tape are characterized by Stockhausen as shots, crashes, and sound bombs. They whizz around the audience and arc over their heads as if they are seated on a battlefield instead of an opera house. There is no real danger as all the munitions are musical.
The sound bombs are dropped by airplanes in Stockhausen's conception. The shots are delivered by flak, and crashes occur when the anti-aircraft guns hit their marks. Inside the sound cube of Oktophonie, most of the bombs fall in the rear away from the stage. The shots generally originate in the lower speakers, often in the front. The crashes cartoonishly corkscrew down to the ground, a movement Stockhausen gleefully controlled in the studio.
Oktophonie was realised in the Studio for Electronic Music of the Westdeutscher Rundfunk, Cologne, in two phases of work: from 23 August to 30 November 1990, and from 5 to 30 August 1991. Studio collaborators were recording engineers Volker Müller and Daniel Velasco-Schwarzenberger, and recording technician Gertrud Melcher. Production was made using a single 24-track tape recorder. A number of synthesizers and modules were used in the production of the sound layers:
In addition, an EMS Synthi 100 was used for control of the spatialization in some layers during the concluding portion.
The last step in composing Okotphonie required spatializing the music over the eight sound channels. The channels are arranged around the audience in a cube, with each corner of the cube containing a cluster of speakers. Each channel ideally has two speakers hung at different angles in order to create the illusions of sonic movement that Stockhausen composed. This speaker array creates six different planes of sound above, below, and around the audience.
In the early 1970s, Stockhausen worked with Peter Zinovieff at EMS to develop a QUEG (Quadrophonic Effect Generator). The QUEG only had four outputs. So Stockhausen also relied on a Yamaha Digital Mixing Processor 7 to complete the octophonic spatialization.
The analog tape at WDR could not contain the full 69 minutes of Oktophonie. Stockhausen split it between two tapes with a bridge.
As accompaniment: