Apparatus and systems for producing a sudden or abrupt sound

摘要

Apparatus for producing a transient sound comprises: a) an electrically operated sound producing device (17); and b) a circuit (2) to be energised from an electrical power source (4) whereby a steep-fronted electrical pulse can be supplied to the device (17) thereby to produce the transient sound. A system may comprise such apparatus and switch means (3) operable to cause the circuit (2) to supply the steep-fronted electrical pulse when the transient sound is required to be produced. Also a system may comprise a plurality of such apparatus and switch means (3) operable to cause the circuits (2) simultaneously to supply the steep-fronted electrical pulses when the transient sounds are required to be simultaneously produced. The invention is of particular applicability for providing "start" signals for athletic and other races. IMAGE