A testament to the interaction between the experimental avant-garde and the countercultural underground, the album was originally released on Elektra, recorded by Jac Holzman (the label's founder, responsible for signing The Doors, Love, and The Stooges) and produced by DNA, a group that included Pink Floyd's first manager, Peter Jenner (the title of Pink Floyd's 'Flaming' is a tribute to AMM's 'Later During a Flaming Riviera Sunset'). Formed in 1965 by three players from the emerging British jazz avant-garde -- Keith Rowe and Lou Gare had played with the great progressive big band leader Mike Westbrook and Eddie Prévost played in a post-bop group with Gare -- AMM quickly evolved from a free jazz group into something decidedly more difficult to categorise. By the time these recordings were made, two more members had joined the group: another Westbrook associate, Lawrence Sheaff, and the radical composer Cornelius Cardew. Then at work on his masterpiece of graphic notation Treatise, Cardew brought with him extensive experience of the post-serialist and Cageian currents in contemporary composition. Using a combination of conventional instruments and unconventional methods of sound production (most famously Keith Rowe's prepared tabletop guitar, but also prepared piano and transistor radio), the group performed improvised pieces often running for over two hours and ranging from extended periods of silence to terrifying cacophonies.

On AMMMusic, long tones sit next to abrasive thuds, the howl of uncontrolled feedback accompanies Cardew's purposeful piano chords, radios beam in snatches of orchestral music. AMM's clearest break with jazz-based improvisation concerned the idea of individuality. Initially through an engagement with eastern philosophy and mysticism and later though a politicized communitarianism, AMM sought to develop a collective sonic identity in which individual contributions could barely be discerned. In the performances captured on AMMMusic the use of numerous auxiliary instruments and devices, including radios played by three members of the group, contribute to the sensation that the music is composed as a single monolithic object with multiple facets, rather than as an interaction between five distinct voices." --Francis Plagne