Performance Practice
of Electroacoustic Music

Helmut Lachenmann



Szenario was realized at the Instituut voor Psychoacustica en Elektronische Muziek (IPEM) of the University of Gent in April and May of 1965. It was first broadcast on June 20 1965 on Belgian Radio BRT3. Lachenmann writes about Szenario that it owes its conception and formal design to the idea of an interplay between “text” and “texture”, wherein “text”, meaning a precisely defined time structure and sound relations, is permeated by broader fields characterized by uncontrollable sound transformations that could theoretically be extended indefinitely (Lachenmann (1996), p. 372).

A concert performance (Köln, 1970) is documented, but the piece was never published. A leaflet by publisher Herbert Post Presse München indicates that publication might have been intended at some point. Later CD releases were all in mono, but the existence of a 4-track tape and the corresponding designation in an early IPEAM publication as well as sketches allow us to assume that the piece was conceived for four channels.

The piece draws partially on instrumental material from Lachenmann’s chamber composition Introversion I (1963). An unpublished text by the composer and two graphic schemes give insight into its conception, albeit these schemes are presumably neither complete nor definitive (Paul Sacher Stiftung, Sammlung Helmut Lachenmann). Lachenmann distinguishes four types of sound material: «Concrete elements» («Konkrete Elemente»), «sounds» («Klänge»), «textures («Texturen»), «noise» («Geräusche»). Each of these contains six to seven segments that appear six to seven times in progressively shorter intervals.

  • The «concrete elements» contain instrumental fragments in which temple block, woodblock, marimbaphone and harp can be distinguished. Processes applied include transposition, reverb and filtering.
  • For the «sounds», reverb and acceleration processes are prominently used. They are still recognizable as distinct frequencies, which is not the case with «textures» and «noise».
  • In the «textures», an aleatory mode of superposition, constantly changing and renewing itself is applied to sound fields that musically act as an ostinato of sorts. Processes used include multiplication, transposition, filtering, feedback, reverse playback, ring modulation.
  • The «noises» are mixed frequencies with no recognizable principal frequency.



Audio material


Since no performance material is distributed by a publisher, IPEM was contacted for information about the tapes held in their archives. A visit to IPEM in January of 2015 revealed the existence of three tapes there:

1. Half-track 4-channel tape, 15 ips: 4 distinct channels, the tape contains numerous splices.

2. Half-track 4-channel tape, 15 ips: mono downmix on channels 1 and 4 (both channels identical), channels 2 and 3 empty. The tape also contains the work Cellotape by Lucien Goethals (1965).

3. Quarter-track 1-channel tape, 15 ips. This is the tape that according to IPEM staff was used for broadcast and copies. It also contains [Jeu de] Miroir[s] de votre Faust [sic] by Henri Pousseur. There are two digital transfers of Szenario available at IPEM (1995 and 2013, the latter published on Metaphon 004-2013).

Institute of Sonology, Den Haag

-Quarter track 1-channel tape, 15 ips. 


Other Archival Material

Paul Sacher Stiftung

The collection Helmut Lachenmann at the Paul Sacher Stiftung has some tapes with material for Szenario. The reels are marked as containing “textures”, as well as individual segments with “Endmaterialien” (final material). There is an unpublished text by the composer on Szenario, as well as an overview of the original musical material used (s. introduction) and a diagram visualizing the “projection of the material”.



The archive at IPEM has several documents relating to the production of Szenario at the studio, broadcast presentation texts, a concert program for a performance in Cologne (1970). There are no sketches or tapes containing material used in the composition process.


Performance report


Exhibiting a great deal of noise, the sound of the available mono file had to be restored. Problematic areas were especially very quiet passages as well as reverb tails and decay. Restoration was done with the iZotope RX4 software. In a first step, the hum at 50 Hz was eliminated. Four harmonic notch filters were used: Linear phase, -48db, -40db, -35db, -30db, very narrow bandwidth. The goal was to find a setting that would not cut the low frequencies. In a second step, a noise profile was generated.

Spatial projection of mono tape

Since at the outset, there was no indication of the existence of a 4-channel tape, the performance team envisioned a manually controlled spatial projection of the mono downmix. This involved a staggered loudspeaker setup with several speakers: symmetrical, direct, close (up and down) and indirect (up and down). The sound projection was conceived to differentiate between articulated material as “text” and “texture” through spatial projection. Direct speakers were used for “text”, while indirect, broadly projecting loudspeakers were used to support textural sound quality and spatial dispersion.

Performance of the 4-track tape

The 4-track tape (s. sources, IPEM, item 1) was digitized by Kees Tazelaar at the Institute of Sonology in Den Haag.

It was performed in concert on January 29, 2015 at ZHdK. The routing used was 1-rear left, 2 front left, 3 front right, 4 rear right. As the sound information in the passage from 3’50 to 4’51 is reduced to channels two and three after the first impulse, a stable sound image in the front seems desirable. Furthermore, circular sound movement at 8’09’’ seems to imply a circular speaker setup.

The tape itself exhibited two peculiarities. First, it starts with an 11-second sine wave test tone at approx. 533 Hz. The reason for such an unusual frequency remains unclear; a speed variation of 6,8% (related to 500 Hz) does not seem plausible. The sweeps in the test tone indicate that it was copied from a second tape machine and not from an oscillator. This could explain certain irregularities. Furthermore, the fourth track was 4.9 dB quieter than the other channels, so it was digitized with 4.9 db more gain (a check against the test tone confirmed this).

Due to the age of the tape there is some crackling and tape noise, as well as some crosstalk between the tracks. This could easily be corrected for performance.

Selected Bibliography

Sabbe, Hermann, Salut für Helmut: Über Lachenmanns elektronisches Tonbandstück Scenario, in Neue Zeitschrift Für Musik: Das Magazin Für Neue Töne, Jan-Feb 2006;167(1): pp. 28-29.

Lachenmann, Helmut, Scenario für Tonband (1965), in Collected Work: Musik als existentielle Erfahrung: Schriften 1966-1995, Wiesbaden: Breitkopf & Härtel, 1996, p. 372.

Schematic Overview

Piece information

Composer Helmut Lachenmann
Year 1965
Studio IPEM, University of Gent
Type Tape, 4-channel (presumably)
Duration 12’26’’
Publisher unpublished


Performance material

n/a, see performance report


Archival material

IPEM, Gent 4-track master tape (presumably master), tape with 2-track downmix, tape with mono downmix; presentation texts for radio broadcast, abstracts, composition report
Paul Sacher Stiftung Graphical overviews, report by the composer, sound material on tape


Commercial releases (selection)

Sub Rosa 2008 An Anthology of Noise and Electronic Music, Volume V, SR270
Metaphon 2014 50 years of electronic and electroacoustic music at the Gent University, Metaphon 04-2013


The editors would like to thank the staff of IPEM at the University of Gent for their generous support and the opportunity to visit their archive, as well as Kees Tazelaar of the Institute of Sonology, Den Haag, for the transfers of the half-track tapes.