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)
6. [sound devices by acoustical characteristics]
7. aerophones
8. lip-vibrated aerophones
9. [lip-vibrated aerophones with conical bore]
10. [lip-vibrated aerophones with conical bore: with valves]
11. tubas

Anotations

Scope note:

Tubas in elliptical shape with a conical bore that widens steadily throughout its length, terminating in a small bell, and having four rotary valves and a French horn mouthpiece. They were originally made to the specifications of Richard Wagner for use in his opera cycle "Der Ring des Nibelungen."