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Harry Pepl * 1945  † 2005
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Composing from improvisation

Real-time Composing / Instant Composing

Real-time Composing or Instant Composing was Harry Pepl's name for his method of turning freely improvised voices, recorded one on top of another, into finished works. It produced string quartets for the internationally renowned Kronos Quartet and the Artis-Quartett as well as the recordings of the Lonely Single Swinger Band. He used both terms interchangeably; from the 1990s onwards he increasingly spoke of Real-time Composing.

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Pepl's concept

For Harry Pepl, composition and improvisation were „an sich zwei getrennte Bereiche musikalischen Schaffens“ [“in themselves two separate areas of musical creation”]. In his method, which he called „instant composing“ or „real-time composing“, the two underwent a „seltene, paradoxe Verschmelzung“ [“rare, paradoxical fusion”].1 He improvised one voice, responded to it with a second and a third, and the result counted as a work. What mattered to him was that nothing was corrected afterwards: „Was in dem Augenblick des Schaffens passiert, bleibt unangetastet.“ [“What happens in the moment of creation remains untouched.”]2 In 2000 he summed it up briefly in a programme text: „Totale Improvisation im Sog der Geschwindigkeit des Augenblicks.“ [“Total improvisation, caught in the pull of the speed of the moment.”]3

In doing so, while playing the instrument, I record what is present in my consciousness during the creative process.

Harry Pepl on real-time composing, Kronen Zeitung, 1994, translated from the German4

The term itself was not new in jazz, as Stefan Heckel rightly points out. As early as 1958 Jim Hall wrote of an “instant composition” in the liner notes to an album by the clarinettist Jimmy Giuffre, meaning an improvised solo part over written-out strings. A few years later the Dutch pianist Misha Mengelberg, a co-founder of the Instant Composers Pool in 1967, used it for music that is assembled anew at every concert.5 Pepl's realisation, however, goes much further: he improvised alone, layer by layer in multitrack recording, slipped into the timbre of any instrument via the MIDI guitar, and the stored MIDI data yielded a score without compositional correction, which ensembles such as the Kronos Quartet and the Artis-Quartett performed in the concert hall.6 In the late work in his home studio in Hernstein (Lower Austria, Austria), what remained was the recording alone, on which he layered every instrument himself.7 Thus, with Pepl, the moment of improvisation became a fixed, performable work, made possible by the technology that became available in the mid-1980s. In his obituary in Der Standard, a Vienna daily, Ljubiša Tošić wrote that the results were “shaped by the old jazz dream of wresting from the moment a musical substance that creates something lasting and thus comes close to composition”.8

Pepl’s way of working is related to that of the Italian composer Giacinto Scelsi (1905 to 1988), a solitary figure of post-war modernism who lived in seclusion in Rome. Between 1939 and 1955 Scelsi created an extensive body of piano works from improvisations at the instrument: he recorded them on tape and assistants transcribed them; from the mid-1950s he used simple electronic instruments to record single-line melodies and mixed them together.9 Pepl had heard about Scelsi in a radio programme and was fascinated; he called him „den in der Höhle Lebenden“ [“the one who lives in the cave”] and drew the comparison with his own work himself.10 As early as 1990 the liner notes to “Schönberg Improvations” named Scelsi’s “method of writing” as an inspiration.11 Some 30 years after Scelsi, Pepl took a similar path, from the piano to electronics, with MIDI guitar and computer instead of tape. Unlike Scelsi, however, he did not have his improvisations prepared into a score afterwards by an assistant.12

Something else is striking, too. In 2009, four years after Pepl’s death, the American guitarist Pat Metheny, one of the best-known jazz guitarists of his generation, recorded his album “Orchestrion”: with the MIDI guitar he controlled mechanical instruments such as marimbas, glass harp and percussion and layered them track by track, “just like Harry Pepl in Instant Composing”, as Heckel writes. Metheny knew Pepl from concerts and workshops in Europe; whether he knew Pepl’s Instant Compositions is not known. Heckel sees a deep kinship between the two guitarists, both pioneers of the MIDI guitar.13 Coincidence or not: what Pepl developed alone in his home studio from the late 1980s shows how early he was onto it. Dave Liebman, the American saxophonist who played on “Schönberg Improvations” in 1989, put it in a nutshell in 2005: this was in the 1980s, “far ahead!!”14

What is astonishing is the effect. The tracks were made one after another, Pepl was alone, and yet the recordings sound as if an improvising jazz band were just coming in together, building in density and reacting to each other in the moment. Layered tracks had existed in jazz before: the American pianist Lennie Tristano recorded two piano parts of his own by overdubbing, and Bill Evans made “Conversations with Myself” this way in 1963.15 Heckel describes the difference: where Tristano, the saxophonist Warne Marsh and their fellow players reacted to one another within a single take, Pepl reacted to himself over several takes in immediate succession, thus adding virtual fellow musicians.16 Daniel Pepl hears in it almost the Wayne Shorter Quartet, the band the American saxophonist led from 2000 with Danilo Pérez, John Patitucci and Brian Blade, known for its collective, floating build-ups of density; in his view this paradox has hardly been grasped to this day.17 A detailed appraisal drawing on jazz studies, the sociology of music and music psychology is on the page The paradox of simultaneity.

A piece to listen to is “Nach Saalfelden” from Pepl’s 2002 Christmas CD. A low register begins alone, after 18 seconds the other parts enter, the music grows denser until around the two-minute mark, pulls back, builds up a second time and fades out, without a single pause. Measuring the sound reveals a curve familiar from a band coming in together, even though each track was made on its own and one after another.18

Nach Saalfelden, Lonely Single Swinger Band

2002

Harry Pepl plays every instrument himself, track by track, one after another, in his home studio in Hernstein, Lower Austria, Austria, and yet the music enters like a band: a low register begins alone, after 18 seconds the other parts join in, the music grows denser until around the two-minute mark, pulls back and builds up a second time. From Pepl’s 2002 Christmas CD.

The tool: MIDI guitar and computer

The starting point was the guitar. With a Roland guitar synthesiser, a pickup on the guitar and a sound module in the rack, Pepl could trigger piano, flute, trumpet, string or drum sounds from the fretboard.19 This allowed him, as he wrote, „obwohl ich nur Gitarre spiele, in die Klangfarbe jedes nur erdenklichen Instruments schlüpfen“ [“although I only play the guitar, to slip into the timbre of any instrument imaginable”].20 He considered himself „so ziemlich der erste“ [“pretty much the first”] in Austria to use a guitar synthesiser.21 The MIDI data ran on an Atari 1040ST with the Notator program, which could typeset notation from it; later he recorded to ADAT and hard disk.22 The estate holds Atari sequencer files dating from as early as February 1986.23

For Pepl, sound was not mere packaging: „Der Sound macht es ganz einfach aus, wozu man inspiriert wird zu spielen.“ [“The sound quite simply determines what you are inspired to play.”] A flute sound made him play differently from a guitar sound.24 An early step was the ECM (the renowned European jazz label) album “Cracked Mirrors” (recorded 1987, released 1988), on which the MIDI guitar plays a defining role and Jon Christensen's drums were added afterwards in Oslo.25 On “Schönberg Improvations” (recorded 1989) Pepl used the MIDI guitar to control a Bösendorfer (Vienna piano maker) 290 SE computer grand piano, first the left hand, then the right.26 Harry Lachner, who wrote the liner notes, called this “a most radical use of technology: to play on a midi guitar connected to a computer just to return to a natural, acoustic sound”: what you hear is not a sampled sound but a Bösendorfer grand piano, played on the guitar. His conclusion: “we should not be puzzled by the technical method but by the musical result.” For the desire to go beyond the limits of one's own instrument, Lachner turned to a remark by saxophonist Dave Liebman, who plays soprano saxophone on the album.27

If you're a great instrumentalist, you want to be able to express anything of the instrument, even beyond the instrument. It's not an instrument any more but an expression.

Dave Liebman, quoted by Harry Lachner in the liner notes to Schönberg Improvations, Amadeo, 1990

How a piece came about

Pepl recorded the first track more or less freely. He improvised the others over headphones to the first, each with a different sound. Sometimes he used the second voice to ask a question, which a third answered.28 For the string quartet for the internationally renowned Kronos Quartet he invented one voice and improvised the other three in response to it.29 A computer generated a score from the MIDI data. Because the machine translated every tiny fluctuation into note values, with very small values and odd time signatures, colleagues edited the notation for the performers: the violinist Andreas Schreiber and the guitarist Helmut Weinhandl the pieces for the Kronos Quartet, Georg Pepl the quartet for the Artis-Quartett.30

Afterwards, the notation itself hardly interested him any more: „Mit MIDI wird das aufgeschrieben, aber das Problem ist, dass mich das dann absolut nicht mehr interessiert, sobald ich es gespielt habe.“ [“With MIDI it gets written down, but the problem is that it no longer interests me at all once I have played it.”]31 Nikolaus Kohler concludes that for Pepl the score is not the precondition of the work at all: the only requirement is the recording.32

Black-and-white photo in the home studio in Hernstein, Lower Austria, Austria: Harry Pepl and the photographer Rainer Rygalyk (right, wearing a cap) between mixing desk, screen, keyboard and shelves full of tapes and cassettes. This is the studio in which Pepl recorded his real-time compositions and the recordings of the Lonely Single Swinger Band. On the left Harry Pepl, on the right Rainer Rygalyk.
Harry Pepl and Rainer Rygalyk in the Hernstein home studioPhoto: musical estate, private collection

Two phases

Stefan Heckel distinguishes two phases.33 From about 1989 to 1994 Pepl wrote commissioned works that were notated and performed: for Ensemble Wien and Ensemble Kontrapunkte at the Musikverein (historic concert hall of the Society of Friends of Music) in Vienna, for the internationally renowned Kronos Quartet (premiered in Graz on 3 December 1991), for STUDIO PERCUSSION graz and for the Artis-Quartett (premiered on 6 May 1993). From the mid-1990s Pepl worked in his home studio in Hernstein, Lower Austria, almost exclusively for the recording itself. This period produced the pieces of the Lonely Single Swinger Band, in which he layered drums, guitars, bass samples, piano and vocals all by himself. Nothing was notated any more; each piece was given a title straight away.34 A large part of these recordings remains unreleased (archive).

Collaboration across distance: Cracked Mirrors

How modern Pepl's way of working was is shown by the making of “Cracked Mirrors”, his album on the renowned European jazz label ECM. It was first planned as a solo work; then Pepl brought in the flugelhorn player Herbert Joos, whom he knew from the Vienna Art Orchestra, the Viennese jazz big band led by Mathias Rüegg.35 Early in 1987 the two, according to the Wochenpresse, a Viennese weekly news magazine, in December 1988, went “without any great plans into a small studio in the Wachau” in Lower Austria, Austria; ECM gives the recording location as Lindner Studio in Furth, and Gerhard Tauber recorded the session in February 1987.36 Pepl was so taken with the result that he called Manfred Eicher. Eicher liked it straight away “but wanted a drummer added”, namely the Norwegian Jon Christensen.37

“So Pepl travelled with the tapes to Oslo, where Jon Christensen sprinkled the drum track over it in the studio,” the paper reported.38 At Rainbow Studio in Oslo, Norway, Christensen played his drums to the finished tracks by Pepl and Joos; Pepl was present and took part in the mixdown with Jan Erik Kongshaug.39 The production thus ran the other way round: overdubs were common practice in the mid-1980s, but the drums were usually recorded first; here they came last.40 The magazine Rillenpost found it “curious” that Christensen's drumming “was laid only afterwards over the already completed duo work”, and praised his sensitivity in playing without contact with his fellow musicians.41

The trio presented the record live in spring 1988, according to the poster probably on Saturday, 16 April, at the Szene Wien, a Viennese venue for concerts, and a few days later at the Posthof in Linz and in Katsdorf, Upper Austria.42

Green poster of the Szene Wien (Hauffgasse 26, Vienna-Simmering, Austria) for the concert by Harry Pepl, Herbert Joos and Jon Christensen on Saturday, 16 April, 8 pm, referring to the LP “Cracked Mirror” on ECM. The year is not on the poster; judging by the weekday and the tour, probably 1988.
Szene Wien poster: Pepl, Joos, Christensen, 1988Photo: musical estate, private collection

Harry Pepl, Herbert Joos, Jon Christensen: trio concert at the Stadtgarten, Cologne, 1989

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The trio whose album was made across two countries, together on stage in Cologne, Germany. Television recording, YouTube channel Fullmax Recordings.

This was unusual for ECM too, where bands as a rule spent a few days together in the studio, in Kongshaug's words “a two-day recording and one-day mix”.43 Since the Covid-19 pandemic, working across locations in a networked way has become a matter of course, with musicians recording together across national borders. From this perspective Heckel sees the method of “Cracked Mirrors” as “almost prophetic”; he calls Pepl “a pioneer of the spatial dissolution of boundaries in musical processes in the field of improvised music”.44 For Heckel the album is at the same time the precursor of the Instant Compositions of the following years.45

The principle of musicians playing to tracks that already exist runs through Pepl's later work. For “Schönberg Improvations” (recorded in Vienna, Austria, in November 1989) he improvised the piano parts at home on the MIDI guitar; in the studio Wolfgang Reisinger, Johannes Enders and Dave Liebman played their parts to the finished tracks, and Liebman had recorded his within an hour of arriving.46 For “Anspannen, Überspannen, Abspannen” for STUDIO PERCUSSION graz (premiered in 1992), Pepl supplied a backing tape with the score, so that in concert, as Heckel puts it, he takes part “as a technical reproduction of a part recorded at an earlier point in time”.47 At the “Habanero-Slide-Show” in 2004, Clemens Salesny, Wolfgang Schiftner and Lorenz Raab played live to tracks that Pepl had selected and thinned out for the purpose in Hernstein, Lower Austria.48 It continues posthumously: since 2015 in the studio and since 2018 on stage, musicians have played to Pepl's original tracks and, as Heckel writes, brought his music “back into real time”.49

Instant Composing in research

Heckel's dissertation “Instant Composing. Das Spätwerk des Jazzgitarristen und Komponisten Harry Pepl” (University of Music and Performing Arts Vienna, 2024) is the most detailed study of the method to date. It asks how improvised music can be fixed and defined as composition, and how Pepl made his Instant Compositions accessible to soloists and ensembles.50 Heckel renders the term as „Komponieren im Ohrenblick“ [“composing in the blink of an ear”].51 He describes how the music changes on its way from the improvised moment through digitisation, quantisation, printed notation, editing and rehearsal to performance and radio broadcast.52 Pepl himself had suggested exactly this comparison: „Interessant wäre bei diesen Sachen der Vergleich zwischen meinem Original, der Notation, und der Version der Interpreten.“ [“With these things, it would be interesting to compare my original, the notation and the performers' version.”]53

Two of Heckel's findings matter in practice. Conventional notation captures Pepl's wave-like phrasing over a steady pulse only inadequately; Heckel therefore proposes listening reports, verbal scores, time-event tables and waveform displays as supplements.54 And performances succeeded above all when the performers had experience of improvisation or knew Pepl's musical language, as Dave Liebman or Wolfgang Puschnig did; where only the written score was passed on, they proved more difficult.55 The literature on Pepl is listed in the literature archive.

Significance for teaching and today's ensembles

The method can be taught, even without the technology of the 1980s: improvise and record one voice, add a second as a response to it, a third with a different sound, and neither cut nor correct the result. With two fellow musicians, Heckel reinterpreted the piece “Dedicated to Michele Noiret's Stockhausen” (2004) from a verbal score, thereby describing a model of how ensembles can work with unnotated music.56 Suggestions for the classroom can be found under For teaching.

Since 2018 Clemens Salesny, Martin Bayer, Andi Schreiber and Valentin Duit have been bringing Pepl's original tracks from the home studio to the stage in multichannel sound and improvising with them. Heckel sees this as proof that music created in the moment can be brought back „in die Echtzeit“ [“into real time”].57 The project is described on the Projects page; anyone who would like to work with Pepl's music themselves will find guidance under For ensembles. The notated works are listed in the catalogue of works.

Notes and sources (57)
  1. Harry Pepl, text on the commission for the internationally renowned Kronos Quartet, former website harrypepl.com and undated information sheet in the estate (p. 4); quoted as the manuscript “Instant Composing. Info-Text für Veranstalter” (1989) in Heckel 2024, pp. 12, 20 and 61. ↩
  2. Ibid. ↩
  3. Programme text for “Zeitraffer” (2000), quoted in Heckel 2024, p. 61. ↩
  4. Bernd Schmidt, portrait “Rastloser Grenzgänger”, Neue Kronen-Zeitung (Styria edition), 28.07.1994, p. 22. ↩
  5. Heckel 2024, p. 21 f. (Hall, liner notes to “Piece For Clarinet And String Orchestra / Mobiles”) and p. 22 (Mengelberg, Instant Composers Pool, founded in 1967 with Han Bennink and Willem Breuker, p. 21, note 13). No source says whether Pepl knew these earlier uses. ↩
  6. Heckel 2024, pp. 11 f., 20, 57, 62 f. and 70; Kohler 2006, p. 141 f. Andreas Schreiber, by contrast, recalls that Pepl “certainly” edited MIDI data afterwards (Heckel 2024, p. 255). ↩
  7. Heckel 2024, p. 154; Kohler 2006, pp. 133 to 135. ↩
  8. Ljubiša Tošić, obituary of Harry Pepl, Der Standard, 06.12.2005, p. 25; translated from the German. ↩
  9. Heckel 2024, p. 51, after the liner notes to Giacinto Scelsi, Suites Nos. 8 and 9 (Musikproduktion Dabringhaus und Grimm, 2015). ↩
  10. Heckel 2024, p. 52 (according to Georg Pepl and Daniel Pepl); that Pepl drew the comparison himself: according to the family (Daniel Pepl, 17 October 2026). ↩
  11. Harry Lachner, liner notes to “Schönberg Improvations” (Amadeo, 1990), after Heckel 2024, p. 52; Kohler 2006, p. 117. ↩
  12. Heckel 2024, pp. 52 and 183. ↩
  13. Heckel 2024, p. 60 (on Pat Metheny, “Orchestrion”, Nonesuch, 2010); translated from the German. ↩
  14. Dave Liebman, “Passings: Harry Pepl”, Intervals, vol. 14, no. 1, December 2005. ↩
  15. Heckel 2024, p. 32 (Lennie Tristano and Warne Marsh, “Intuition”) and p. 61 (Bill Evans, “Conversations with Myself”, Verve 1963). ↩
  16. Heckel 2024, pp. 33 f. ↩
  17. Listening comparison and assessment by Daniel Pepl, 17 October 2026; he described the same impression of a band improvising together as early as Concerto 2/2009, p. 44. ↩
  18. Signal analysis of the SoundCloud version, measurement made for this archive (signal analysis: loudness according to EBU R 128, spectral flux, frequency bands, stereo image), October 2026; measurement data on request; recording on SoundCloud, account fullmax, uploaded on 25 December 2016. ↩
  19. Heckel 2024, pp. 54 and 77 to 79. For 1989 Heckel names an Ibanez guitar with the Roland GK-2 pickup and the GR-50 guitar synthesiser. ↩
  20. Manuscript “Instant Composing” (1989), quoted in Heckel 2024, p. 54. ↩
  21. Kohler 2006, p. 121. ↩
  22. Heckel 2024, pp. 62 and 78 to 80. ↩
  23. Eight sequencer files dated 6 February 1986 in the digital holdings of the estate. The sources date the beginning of the MIDI work differently: Kohler 2006 (p. 142) to the mid-1980s, Heckel 2024 (pp. 15 and 83) to 1988 or the transition period 1988/89. ↩
  24. Kohler 2006, p. 121. ↩
  25. Heckel 2024, pp. 83 and 91 f.; Kohler 2006, p. 113 f. ↩
  26. Kohler 2006, p. 115; Heckel 2024, pp. 103 to 113. ↩
  27. Harry Lachner, liner notes to Harry Pepl, “Schönberg Improvations”, CD booklet, Amadeo 843 086-2 (PolyGram, Vienna, 1990); the Dave Liebman quotation also appears there, without saying where Liebman said it. ↩
  28. Heckel 2024, pp. 11, 62 f. and 116. ↩
  29. Harry Pepl, text on the commission for the internationally renowned Kronos Quartet (as in note 1). ↩
  30. Heckel 2024, pp. 80 to 82 and 123 to 126. ↩
  31. Kohler 2006, p. 121. ↩
  32. Kohler 2006, p. 142. ↩
  33. Heckel 2024, pp. 16 and 84 f. ↩
  34. Heckel 2024, pp. 154 and 158 f.; Kohler 2006, pp. 133 to 135. ↩
  35. Heckel 2024, p. 92; Kohler 2006, p. 113. ↩
  36. Wolfgang Kralicek, “Saitensprünge”, Wochenpresse no. 49, 9 December 1988, p. 55; Heckel 2024, p. 92; recording location according to the ECM catalogue; engineer according to the album credits (Discogs 1972108). ↩
  37. Wochenpresse, 9 December 1988, p. 55; Kohler 2006, p. 113; Heckel 2024, p. 228 (interview with Heimo Steps). ↩
  38. Wochenpresse, 9 December 1988, p. 55. ↩
  39. Heckel 2024, pp. 90 and 92; mix according to the album cover (“Mixed at Rainbow Studio, Oslo”), after Kohler 2006, p. 113. The exact date of the Oslo session has not been handed down. ↩
  40. Heckel 2024, p. 100. ↩
  41. Rillenpost, quoted in Heckel 2024, p. 101. ↩
  42. Poster of the Szene Wien from the estate (without year; 16 April fell on a Saturday in 1988); Heckel 2024, p. 94 f. (Posthof Linz, 20 April 1988, and Katsdorf). ↩
  43. Jan Erik Kongshaug interviewed in Tape Op, no. 91, September 2012. ↩
  44. Heckel 2024, p. 91 f. ↩
  45. Heckel 2024, pp. 83 and 102. ↩
  46. Kohler 2006, p. 115; Heckel 2024, pp. 111 f. and 246 (according to Richard Österreicher jun.). ↩
  47. Heckel 2024, pp. 137, 140 and 143. ↩
  48. Heckel 2024, p. 155 f. ↩
  49. Heckel 2024, pp. 12, 156 to 158 and 259. ↩
  50. Heckel 2024, p. 15. ↩
  51. Heckel 2024, pp. 19 and 51. ↩
  52. Heckel 2024, pp. 123 to 125 and 136. ↩
  53. Kohler 2006, p. 122. ↩
  54. Heckel 2024, pp. 99, 159 to 162 and 172. ↩
  55. Heckel 2024, pp. 174 to 176. ↩
  56. Heckel 2024, pp. 272 to 282. ↩
  57. Heckel 2024, pp. 163 to 170. ↩

Last updated: 19 Oct 2026