Geophone (musical instrument) Geophone (musical instrument) The geophone is a percussion instrument, invented by the French composer Olivier Messiaen for use in his large composition for piano and orchestra entitled "Des canyons aux étoiles…" ("From the canyons to the stars…"). It consists of a drum filled with thousands of small lead pellets, and is played by swirling it around slowly so that the noise of the pellets resembles the sound of dry shifting earth. Messiaen commissioned a Parisian instrument maker to construct one to his design, and he carried this instrument worldwide to early performances of the piece (which was given its first
Recorder (musical instrument) in each hand. In others, flutes of the same length have differing hand positions. In a final case, the pipes are parallel, in contact with each other, and differ in length. While the iconographic criteria for a recorder are typically a clearly recognizable labium and a double handed vertical playing technique, such criteria are not prescriptive, and it is uncertain whether any of these depictions should be considered a single instrument, or constitute a kind of recorder. The identification of the instrument depicted is further complicated by the symbolism of the aulos, a double piped instrument associated with the satyr