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. reeds (aerophones)
9. reedpipes (confined aerophones)
10. [reedpipes with double reed]
11. [reedpipes with double reed: with conical bore]
12. [reedpipes with double reed: folded conical bore]
13. bassoons

Anotations

Scope note:

Bassoons pitched below the regular bassoon, with the tube usually, though not always, bent back upon itself several times in order to reduce the overall length and bring the keys within convenient playing position.