Clarence Barlow
Data Composer Extraordinaire

Clarence Barlow: Data Composition Techniques

with Scot Gresham-Lancaster / 16 August 2020 / 16:58

CLARENCE BARLOW and host Scot Gresham-Lancaster have know each other for decades and over the years Scot's admiration for Clarence's amazing body of work and research has only grown. In this podcast they talk over some of that work with a focus on the pieces at the Art/Science boundary. Clarence speaks at length about many of his challenging new ideas regarding techniques for using data in new ways to construct epic and comprehensible auditory experiences. He eschews electronics and converts his data explorations to acoustic instruments. This makes his approach most approachable and singular at the same time.

We talk initially about his new piece Coronialus (2020) which commemorates the fact that the Beethoven year 2020 has been ridden with the new coronavirus. Generated by an electronic transformation of a time-stretched sound recording of the first two chords of Ludwig van Beethoven's Coriolanus Overture Op.62, the individual samples of the stereo recording stretched – for three versions of the piece (see below) – from 6 to 75, 91 and 112 seconds were manipulated by information contained in the genome of the coronavirus. This genome contains exactly 29,903 nucleobases, identified as adenine, guanine, cytosine and uracil. Further, the molecules of these four bases each consist of a typical number and arrangement of atoms of the four chemical elements hydrogen, oxygen, nitrogen and carbon. In Coronialus, the molecular arrangement as well as the valency and atomic number in the periodic table of each individual atom in the genome form the basis of a continuously micro-time-varying downwards frequency transposition through specific sample repetition. This technique in turn led to a second temporal expansion of the already elongated sound recording. Three versions of Coronialus have been made; their durations are 4'43", 5'34" and 7'18". The transformed second Beethoven chord begins just after the middle of the piece. The title - an anagram of 'Coriolanus' - contains the word 'corona' as well as the abbreviation RNA of the acid containing the genome.

Here is the Coronialus version at 7'18" Download
Here is the Coronialus version at 4'43" Download

Here is a pointer to a pdfs of various papers of his

  • Visualising-Sonifying

  • On Musiquantics 2012

  • Quantification

  • He also provided this explanation of the following score to Stochroma

    Composed in April 1972 with a computer at the University of Cologne, this piano piece has a duration that I was only able to determine precisely in 2020 with the help of a computer. Although I have been familiar with computers and their programming since 1971, until now I had no access to one that could process very large numbers - the durations of my piece are expressed in seconds as the products of powers of two, those of -2215 (very short) to +97 (very long). Sounds are given as note names. There are always pauses in between, which are shown as four connected hyphens. The durations of the sounds and pauses take the form N times a power of 2, e.g. the fourth pause 12X2 ** 58 (seconds). I was able to calculate a long time ago that this duration corresponds to 109,603,884,235 years, 35 days, 17 hours, 48 minutes and 48 seconds. The problem was adding up all 10,000 permanent values. Now it finally turned out that the total duration of the piece is 1,291,393,870,437,209,181,492,178 years, 182 days, 2 hours, 33 minutes and 46.361730597612109 .. seconds. Stochroma may be performed by any number of pianists in excerpts of any length. The title is made up of 'stochastic' and 'chromatic'. The name of Stockhausen, my composition teacher at the time (1972) is also in there.

    In 2001, the composer Tom Johnson exhibited a score page in the Queen Sofia Museum in Madrid for several weeks. Clarence's website

    I would be remiss if I did not include a pointer to Clarence Barlow's early masterwork Çoğluotobüsişletmesi, here played by pianist Herbert Henck

    Bio: CLARENCE BARLOW - 1945: born into the English-speaking minority of Calcutta, going there to school and college, studying piano, music theory and natural sciences. 1957: first compositions. 1965: graduated in science at Calcutta University, thereafter active as conductor and music theory teacher at the Calcutta School of Music. 1968: moved to Cologne, studying (until 1973) composition and electronic music at Cologne Music University. 1971-1972: studied also at the Institute of Sonology, Utrecht University. 1971: began to use computers as a compositional aid. 1982: initiated, 1986 co-founded, 1986-1993 and 1996-2002 chaired GIMIK: Initiative Musik und Informatik Köln. 1982-1994: in charge of Computer Music at the Darmstadt Summer Courses for New Music. 1984-2005: lecturer on Computer Music, Cologne Music University. 1988: Director of Music, XIVth International Computer Music Conference, held in Cologne. 1990-1991: visiting professor of composition, Folkwang University Essen. 1990-94: Artistic Director, Institute of Sonology, The Hague Royal Conservatory. 1994-2006: Professor of Composition and Sonology at the same conservatory. 1994-2010: member of the Académie Internationale de Musique Electroacoustique in Bourges. 2005-2006: visiting professor of composition, School of Music and Performing Arts ESMAE in Porto. Since 2006: Corwin Professor and Head of Composition, Music Department, University of California Santa Barbara.

    Longer BIO here

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