What defines idiophones in the context of musical instruments?

Idiophones are defined by the principle that they produce sound primarily through the vibration of their own material without the need for external aids such as air, strings, or membranes. This means that when an idiophone is struck, shaken, or otherwise manipulated, the body of the instrument itself vibrates to create sound. Instruments in this category include marimbas, cymbals, and xylophones, among others.

The nature of idiophones distinguishes them from other classes of instruments, such as aerophones, which rely on air to produce sound, and chordophones, which require strings. The unique characteristic that defines idiophones emphasizes their self-vibrating quality, allowing them to create distinct tones based merely on the material from which they are made and the way they are played. This self-sufficient sound production is what allows idiophones to stand out in the classification of musical instruments.