Sum is the debut album of Werken, one of the aliases of Tilman Ehrhorn known for his releases on Mille Plateaux and Resopal Schallware. Working full time as saxophone and reed player, composer, producer and sound designer Tilman Ehrhorn is a highly regarded jazz artist who also took roots in the electronic world. Among teaching, giving jazz clinics and regular work in theater, tv-, radio-, and cd- productions he has established himself as a composer as well as a performing artist in clubs, at festivals and for concert tours all over the world.This release introduces an experimental and ambientish dubby side of his producing skills. Almost every sound has been generated on a modular synthesizer. Some important developing tools within the synth are sine- and noiseoscillators, with which also most of the percussion sounds are built. The majority of tunes are crossfading to the following; the progress of the album ranges from the opening track to its closing reprise like of one piece. In many parts of the tracks, beats are used rhythmically free to interrupt a pulsing soundpad, which is a main element of the music. Some minimal changing figures are taking hold to break up continous sequential patterns. The non-conventional manner of generating sounds as well as using elements of chance within the production process creates similarities with the improvisational niveau of jazz and contemporary composed music.