Karl­heinz Stock­hausen —  Kon­tak­te (1958)

Kon­tak­te man­i­fests Stockhausen’s con­cept of group-com­po­si­tion, in which ser­i­al com­po­si­tion­al process­es no longer lead into a “spo­radic music” of sin­gu­lar iso­lat­ed events, but organ­ise the devel­op­ment or sta­tis­ti­cal sta­t­ic of sound events into high­er form sec­tions (“groups”). Stockhausen’s refined spa­cial com­po­si­tion rich with rotary move­ments, is espe­cial­ly impressive. 

Bernd Alois Zim­mer­mann —  Trat­to II (1970) for 4‑channel audiotape

In his piece Trat­to II, Zim­mer­mann immers­es the lis­ten­er with a four chan­nel lay­er­ing of sine tones, whose calm move­ment ren­ders Zimmermann’s con­cept of time and space dila­tion — Zim­mer­mann called this “the spher­i­cal gestalt of time” —  experiencable.

We dis­cussed the music-aes­thet­i­cal explo­sive pow­er of these com­po­si­tions dur­ing this con­cert and talk evening. Mar­tin Sup­per, who is renown as musi­col­o­gist and com­pos­er of elec­troa­coustic music and sound art, gave insight into his inter­pre­ta­tion of these two most influ­en­tial works of mul­ti chan­nel audio­tape music of the late 1950’s.