Ab2-Bb2 (downtrill). Cooper, L. Hugh. The Double Reed 2/4 (April 1980): 27. Same as Ab2-Bb2 downtrill on Cooper p. 51.

x x x | x x o      x x x | x x x
   w   Bb             w   Bb

Ab2-Bb2. Christlieb, Don. Pictoral Fingerings for Bassoon. Published by author, 1966, p. 21. Cooper, L. Hugh. The Double Reed 2/4 (April 1980): 29. Timm, Everett LeRoy. The Woodwinds; Performance and Instructional Techniques. Boston: Allyn and Bacon, 1964, p. 172. Same as first Ab2-Bb2 trill on Cooper p. 36.

   (Eb)
x x x | x tr x Ab
   w
  (D)

Ab2-Bb2. Elliot, Thomas C. In Klimko, Ronald. Bassoon Performance Practices and Teaching in the United States and Canada. Idaho: University of Idaho, 1974, p. 65.

    Eb
x x x | x tr x Ab
         E
   D

Heckel-System (German) Bassoon Trills and Shakes by Note Names