Schat was born on 5 June 1935 in
Utrecht. He studied composition with
Kees van Baaren (1952–1958) at the Utrecht Conservatoire and Royal Conservatory of The Hague. Then he studied with
Mátyás Seiber (1959 London) and with
Pierre Boulez (1960–1961
Basel). His 1954 Passacaglia and Fugue for organ was a notable early student work. Under van Baaren and Seiber, he combined traditional forms with
dodecaphony in his 1954
Introductie en adagio in oude stijl and 1957 Septet. He won the 1957
Gaudeamus International Composers Award. Boulez led him to a more radical, strict form of
serialism. Schat was regarded as one of the outstanding representatives of the avant garde in the Netherlands. In the late sixties Schat became associated with the
Provo movement; their publications were printed in his cellar. He was involved in the notorious 1969 "notenkrakersactie" (Nutcracker Action) in which a group of activists interrupted a concert by the Concertgebouw Orchestra, demanding an open discussion of music policy. That same year, Schat contributed, together with the composers
Reinbert de Leeuw,
Louis Andriessen,
Jan van Vlijmen, and
Misha Mengelberg, and the writers
Harry Mulisch and
Hugo Claus, to
Reconstructie, a sort of opera, or "morality" theatre work, about the conflict between American imperialism and liberation. In February 1969 he co-founded the Studio for Electro-Instrumental Music (STEIM) in Amsterdam. Among his most widely noted works are
Thema (from 1970) and
To You (from 1972).
To You was performed at the
Holland Festival. The 1970s also brought Schat's most distinctive contribution to 20th-century music theory, the "tone clock". It lends its name to a translation of his collected essays,
The Tone Clock (Contemporary Music Studies) (1993, Taylor and Francis Verlag, ). Schat died in
Amsterdam on 3 February 2003, from cancer. ==Composition==