Tunnel for 4 channel tape (11') 1995 Tunnel for four channel tape was commissioned by Warren Spears of Nyt Dansk Danseteater for the ballet CMXCV . Another of my four channel pieces, Cobra, was the basis for the ballet. One day Warren Spears called me and asked if I could extend the long final drone of Cobra an extra ten minutes. After pondering the idea, I decided to write a new work consisting of a single long note. This task may seem simple, but for me it meant trying to create a long drone note which would undergo constant process of change: always the same yet never the same. I used a number of recordings of water, fire, crowds, children at play, etc. These recordings were processed by a computer using the programming environment Csound to apply complex filtering to the recorded sounds. The computer was used to extract the same note from these various sound sources. This technique might be compared to a kind of tube or tunnel, which, though creating no sound of its own, colors any sound passing through it. In addition, the computer was used to create a gradual transition and transformation from one state to the next, passing through the tunnel. The ballet CMXCV was premiered in Copenhagen in September 1995 .