The material of the four-track tape composition Mandelkern consists exclusively of prerecorded flute sounds that were, in part, modulated through granular synthesis. The piece has six short parts, which are similar to or differ from the natural flute sound in different degrees. There are also contrasts between static movement and organic development. The title "Mandelkern" (literally in German: almondheart) refers to a part of the brain analogous to the hippocampus, which has vital control functions and where one suspects that emotional impulses are triggered. The composition plays with various grades of distance from natural flute sounds as well as oppositions between static, block-like progressions and organic movements. Mandelkern was conceived for four loudspeakers, but not primarily to achieve an effective and well-sounding distribution of sound within a space. Rather, the loudspeakers were treated as instruments, forming an ensemble of different sound sources that work together.