Abstract: A sound-generating unit (30) is encased within the body (20) of an article (10) which is to be launched by a burst of compressed and/or pressurized fluid (15) from a fluid launching device (11). The sound-generating unit (30) has the three main elements of a piezoelectric electromechanical transducer (32), a sound-generator electronic circuit (40), and a speaker (42). The body (20) of the article to be launched has a bore to receive the burst of fluid (15). The piezoelectric element (32) is positioned within the bore in alignment for receiving the impact of the burst of fluid (15). The piezoelectric element (32), the speaker (42) and an electrical energizer (36) are connected to the sound-generator circuit (40). Upon being impinged by a burst of fluid (15) projected into the bore of the body (20), the piezoelectric element (32) minutely deforms and generates a voltage that is processed by the sound-generator circuit (40) into a desired sound-effect signal that drives the speaker (42).