A sound wave is a vibration that travels through a solid, liquid or gas such as the air or water. A loud sound has a large amplitude, a high pitched sound has a high frequency. Musicians and ...

The TRANSMISSION of acoustic energy through a medium via a SOUND WAVE. See: SOUND, SPEED OF SOUND. Compare: ACOUSTIC RADIATION. The levels of outdoor NOISE, whether they are intrusive or the normal ...

Fourteen police officers were injured by an extremely loud siren at an anti-AfD demonstration in Berlin's Wittenau district, ...