We have to start the concert at 8:00 and we have to stop sometime because the halls are rented for a certain time but the music goes on in your mind before and after you play. It’s really just an agreement you make to stop at a certain time. On record, it goes for 40 minutes because an album has these dimensions. It’s just an agreement. But really the music goes on.

Interview with Kraftwerk. Ralf Hütter and Florian Schneider talking with Synapse Magazine. September, 1976. On a side note, Ralf und Florian is a fantastic album.