Tremolos on bassoon

Pitch/interval	Listen
F3/minor 3rd
F3/major 3rd
B3/minor 3rd
C4/major 3rd
G4/minor 3rd

Tremolos on contrabassoon

Pitch/interval	Listen
G1/major 3rd
G1/perfect 4th
C2/major 3rd
D2/minor 3rd