Perhaps the most iconic and "classic" of AMM albums, recorded at The Crypt in London in 1968 with AMM as the quartet of Cornelius Cardew on piano & cello, Lou Gare on saxophone and violin, Christopher Hobbs on percussion, Eddie Prevost on percussion, and Keith Rowe on guitar & electronics.

A collection of Feldman compositions primarily for piano as recorded by his earliest interpreters: Cornelius Cardew, John Tilbury, David Tutor, Cantilene Chamber Players, and Feldman himself.

Their first release in 2000 performing Cornelius Cardew's "Treatise", for 20 years the Formanex quartet of sound artists, conceptualists and experimenters Anthony Taillard, Christophe Havard, Emmanuel Leduc, and Julien Ottavi are heard here in collaborations with Keith Rowe, Kasper T. Toeplitz, Ralf Wehowsky, Seth Cluett, Michael Pisaro, Radu Malfatti, &c.