Organum is the project of elusive composer and visual artist David Jackman. An artist who began his career in the U.K. with experimental group Scratch Orchestra alongside Cornelius Cardew. This seminal improvisational group was also the breeding ground for Amm and the New Zealand percussion composer Phil Dadson.

Jackman's work as Organum was documented on limited-edition vinyl LPs in the '80s, and in the '90s he released numerous CDs. The albums Submission, released by Complacency in the U.S., and Veil of Tears, on Matchless, exhibit a strongly minimalist aligned music, with an attention to the sonic effects of massed string drones and metal percussion. Many Organum recordings were made as location specific happenings, taking advantage of unusual reverberant spaces to enhance the music performance, such as tunnels, caves, and a highway overpass, as well as many outdoor natural environments.

Highly regarded in avant-garde music circles, he has worked with members of Nurse With Wound, Jim O'Rourke, Robert Hampson of Main, and Christophe Heenmann of H.N.A.S. This dark ambient drone music that at times recalls the minimalist violin drones of Tony Conrad or the electronic soundscapes of Mophogenesis, although it is often called post-industrial, it is far from the futuristic imagery conjured by such a tag. In fact, this music has roots in Medieval and Eastern ritual music, hence Jackman has titled one of his works Kammer, which references the early music genre of the same name.

On the collaboration CD Crux + Flayed on Matchless, Jackman and percussionist Eddie Prevost used electronics to transform sounds of a drum and cymbal improvisation that results in a dense drone alive with overtones and harmonics. This approach differed from the heavily reverberated strings improvisations of prior works. Akin to the work of David Toop and Max Eastly, in that it is inspired by British minimalism, free improvisation, and sound sculpture, the music is Zen-like and can be simultaneously elating and dark. ~ Sylvie Harrison, Rovi