Noise is a widely recognized problem and health concern in the modern world. Given the importance of managing noise levels and developing suitable 'soundscapes' in contexts such as industry, schools, or public spaces, this is an area of active research for acousticians. But noise, in the sense of dissonance, can also be used positively; composers have employed it from Baroque music to Rock feedback; medicine harnesses it to shatter kidney stones and treat cancer; and even themilitary uses it in (real and rumoured) weapons.Mike Goldsmith looks back at the long history of the battle between peop