De natura sonoris (On the nature of sound) is the title of three works by the Polish composer Krzysztof Penderecki.
As the title suggests, it is a vigorous exploration of wildly divergent orchestral effects and dynamics.
It was premiered on 7 April 1966 at the International Festival of Contemporary Art in the French town of Royan.
Penderecki again took up the theme of vividly contrasting orchestral colouration, including unusual percussive effects: an iron bar is struck by implements such as a hammer and a saw.
In 1975 the composer recorded both works with the Polish Radio National Symphony Orchestra for EMI.