A styrophone is an acoustic device made from expanded polystyrene foam (often referred to by the genericized trademark Styrofoam). There are at least two varieties:
an acoustic musical instrument a type of loudspeaker
Musical instrument
The musical Styrophone is a type of friction idiophone created by Robert Rutman in the 1990s as a parody of his well-known sheetmetal instrument, the Bow Chimes. It consists of a foam box from which protrude a series of thin brass rods played with a violin bow. Rutman's ensemble would build the impromptu instruments prior to a performance, and then destroy them through the process of their use. Other versions have been created with wooden sticks used in place of metal."Frictioned Foam" by Liam Mooney
Styrophone loudspeaker
An inexpensive alternative to heavy-duty amplification systems, the Styrophone loudspeaker is usually of a cheap homemade variety that consists of a crystal earpiece attached to a cone made from a foam cup or sections of packing material."Styrophone Crystal Loud Speaker" from Peebles Originals
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