After this key experience, Geisse bought toy plastic saxophones for the members of his band and threw away his original plan to play jazz standards.

The avant-garde combo "Brother Virus" which along with Geisse included Werner Klausnitzer, Patrick Scales, and Maurice de Martin, achieved fame at the end of the 1980s.

On a renewed search for natural structural references, he received suggestions and impetus from the Institute for Medical Psychology at the Ludwig-Maximilian University (LMU) in Munich on the theme "time and its perception".

The classic compositional parameters of tempo, meter, and rhythm are pushed into the background by this broadening of perspective through a psychological perception of time.

They include: Richard Barrett, Marty Cook, Phil Durrant, Vinko Globokar, Barry Guy, Franz Hautzinger, Jason Kahn, Thomas Lehn, Michael Lentz, George Lewis, David Moss, Günter Müller, Olga Neuwirth, Phill Niblock, Evan Parker, Giancarlo Schiaffini, Ignaz Schick, Ed Schuller, Mike Svoboda, Gary Thomas, Wu Wei, Xu Fengxia.

Gunnar Geisse has worked with or played works of Hans-Jürgen von Bose, John Cage, Peter Maxwell Davies, Fred Frith, Gérard Grisey, Hans Werner Henze, Tom Johnson, Helmut Lachenmann, Anestis Logothetis, Chico Mello, Josef Anton Riedl, Gioacchino Rossini, Dieter Schnebel, James Tenney, Kurt Weill, Jörg Widmann, Christian Wolff, and Udo Zimmermann.