Having studied at the Conservatory in Biel and Zurich, Hans Koch began his musical career as a classical clarinetist, working from 1973 to 1980 at the Music College of Winterthur. In 1978, he met Martin Schütz, also at the Conservatory, and they formed a jazz trio at the beginning of the 1980s, finally settling with the drummer Marco Käppeli. Moving through the Horace Silver and John Coltrane repertoire, they were later influenced by Albert Ayler, Steve Lacy, Anthony Braxton and Evan Parker, gradually moving to compose their own pieces. Performances eventually led to a recording of the trio on ECM and then a second disc the following year (1988) on Sound Aspects. In 1985 he won the best soloist award at the Jazzfestival Lugano and in 1986 was awarded the "Kulturpreis from the city of Biel".
During the same period, Koch was also a member of Werner Lüdi's Sunnymoon, along with Martin Schütz, Stephan Wittwer and Paul Lovens. In 1987 he undertook a 6-month residence in New York with funding from the Kanton of Bern and played in a wide variety of situations: with Andrew Cyrille, Butch Morris, Shelley Hirsch and David Moss among many others. This resulted in regular groupings such as a trio with Cyrille, a Swiss tour with Moss and Jim Meneses and performance at Willisau and Nickelsdorf and a recording for FMP of X-Communication (Morris, Hirsch, Schütz, Lovens, Hans Reichel, Jason Hwang and J.A. Dean). In 1988, Koch was a member of the Cecil Taylor European Orchestra, the recording of which was released in the much-prized In Berlin box set from FMP.
Hans Koch's solo CD, Uluru was recorded in 1989 and at the end of 1991 CHOCKSHUT (a near anagram of Koch and Schütz) was recorded, a sextet that included Fredy Studer. This was the beginning of the trio "Koch-Schütz-Studer", though their first recording with the descriptive and provocative title of Hardcore chamber music was not recorded for another three years, by which time Koch was working with electronics as an extension of his reeds, as well as with sampling/sequencing. In the ten years that have followed, the trio has recorded frequently and collaborated with a wide variety of musicians: from Egypt, from Cuba, with DJs, and with poetry/spoken word.
In addition, Hans Koch has collaborated in radio-plays and film, for example:
playing the music of the Swiss film "Höhenfeuer" by Fredi Murer
composed the film music for "Tupamaros" from Rainer Hoffmann and Heidi Specogna
created the music for the radio-plays for DRS2, "Die Amsel" from Robert Musil,
"Der Mann des Zufalls" from Yasmina Reza and "Hang und Riss" from Alex Gfeller.
In 2000, Hans Koch undertook a 6-month stay in London with funding from the Kuratorium Aargau and played with frequently with British free improvisers, some meetings of which are documented on the Intakt CD London duos and trios, while his sitting in the the London Improvisers Orchestra was releaed on Emanem. More recently he has formed a duo with Bertrand Denzler which has issued a CD on Ambiances Magnétiques and toured the USA in October 2003.