Gaiaphones (from Gaia, the Greek goddess of the Earth, and phone, meaning 'sound' or 'voice') is a term coined by Steve Mann from the University of Toronto. The group includes all musical instruments involving the vibration of solids to produce sounds. For purposes of classification in this wiki, gaiaphones are the largest and first group of instruments in our expanded Hornbostel-Sachs system meaning all other classifications are pushed back. The other top-level categories are based off the other elements: hydraulophones (liquids, usu. water), aerophones (gases, usu. air, e.g. oxygen and heilium), plasmaphones (plasma, includes instruments using electric discharge and fire), and quintephones (idea or information such as synthesized sounds).
- 100 Gaiaphones
- 110 Idiophones
- 120 Membranophones
- 130 Chordophones
The term gaiaphone was coined by Steve Mann at the University of Toronto in his article, Natural Interfaces for Musical Expression: Physiphones and a physics-based organology. "The original three-level categories now become subcategories under solid instruments. Solid instruments might be called 'stereophones' from Greek 'stereo' meaning 'solid', but since 'stereophone' already has another meaning, 'Gaiaphones' is more appropriate (Greek goddess of the earth - the Greeks used Earth, Water, Air, and Fire to refer to the four states of matter)."