Abstract: A system is provided for selectively detecting and indicating impacts on a base surface, said system comprising at least one detector unit and at least one indicator unit. Said detector unit comprises one or more capacitors between the plates of which an elastic material is inserted, the distance between said capacitor plates as well as the dynamic spring rate of the elastic material being adjusted to the type of impact to be detected and/or the nature of the base surface, and said detector unit is connected to a voltage source via a resistor having high resistance which is chosen with respect to the speed of the impacts to be detected.