Patent attributes
An electro-acoustic device for creating patterns of particulate matter comprises a housing (2) one end of which is closed and the other end of which is open, a diaphragm (10) extending across the housing (2) at or adjacent the open end of the housing to define and close a hollow interior to the housing, a mass of particulate matter (34) located on the diaphragm (10), and, within the hollow interior of the housing (2), an electro-acoustic transducer (26), the arrangement being such that, in use with the diaphragm (10) extending horizontally and on activation of the transducer (26) by an audio signal, the acoustic output therefrom excites the diaphragm (10) and creates a pattern in the particulate matter (34) thereon representative of the audio signal.
