some bassoons have a white, ivory ring round the top of the bell joint. these are german bassoons (called ‘heckel’). french bassoons (called ‘buffet’) do not have this ring, and also sound quite different to german bassoons. bassoons have keys to help the player to cover all the holes, but these keys do not use the boehm fingering system like the other woodwind instruments. german bassoons use a system called the heckel system, and french bassoons use the buffet system.