On a table is an old oscillator connected to a speaker and a 480 Hz tuning fork. The oscillator frequency is stable at 479.5 hz. When the tuning fork is aleatorically struck by the solenoid, a beating pattern appears. We then hear the friction between the two oscillations, the friction between the electronic and the acoustic, the friction between different periods of the history of sonic research. This humble piece is an homage to two people I admire : sound artist Alvin Lucier (1931-) who worked extensively with oscillators and physician Hermann von Helmholtz (1821-1884) who used the tuning forks for sound analysis and who was among the first to theorize on the beating patterns between frequencies.