Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Furnishings and Equipment (hierarchy name)
4. Sound Devices (hierarchy name)
5. sound devices (equipment)

Anotations

Scope note:

Acoustic devices composed of a toothed spinning wheels that create tones if a blade or plectrum is held against them. Tones varying due to the speed or size of the wheel. Invented by French physicist Félix Savart. His invention was later adapted as a component of the tone wheel organ.