Here is the drawback to the bassoons. The technique of the bassoons is the least refined of any of the woodwinds. The modern advances in keywork that grace the flutes, oboes, clarinets, and saxophones were never applied to the bassoon. In some ways, the bassoon hasn’t changed much since the early Romantic era (or even earlier!). Players have to go to amazing lengths to produce what is relatively easy on the other instruments (and they do it without complaining).
The lowest half-octave is almost entirely controlled by the left thumb. This one finger plays four notes by itself (and two more notes are controlled by the left little linger for a total of six notes for two fingers). Technique will necessarily be slower down here. This said, the only impossible trill on the bassoon is one between the lowest D-flat and E-flat (and some clever bassoonists/manufacturers have devised a way around this).
The highest range also presents some technical problems. Diatonic and chromatic passages are fairly easy, but fast arpeggiated figures become much harder (again these notes are controlled by the same left thumb that controls the lowest half-octave). All this said I do find the upper register of the Bassoon one of the most beautiful sounds of all the winds. Sustained melodies and harmonies up here are best. Notes above the high C become progressively harder. Most bassoonists will dread a high E (and won’t attempt the high F!).
Flicking – A relic of an older time, the Bassoon’s octave key system is archaic, awkward, and doesn’t work in some cases. The current octave system utilizes multiple keys for the left thumb. Because of this, the upper register can be tricky. This said, some innovative bassoonists and instrument manufacturers and repairmen have developed a modern octave key system that works remarkably well. I hope to see it standard in the future.
Arthur Weisburg explaining the new octave key system for the Bassoon.
Large jumps on the bassoon are quite common, and thought of as normal occurrences. Tremolos are almost unheard of (though not impossible). The bassoon can produce the most crisp and dry staccato of any instrument save the Xylophone. This effect has been utilized since the bassoon came into being.
Contrabassoon technique is even less refined than that of the Bassoon. As a Contrabassoon player, I can vouch that technical passages can be very awkward on the instrument. Notes above written middle C all require substantially different and more complex fingerings than that of the Bassoon. Thankfully, as the lowest instrument in the orchestra or band, the Contrabassoon is rarely called upon to play complex parts.
The bassoon is the first instrument we have that uses multiple clefs. For a bassoonist, both bass and tenor clef are a matter of life. Tenor should be used for any passages that use too many ledger lines above the bass clef. In rare cases, the use of treble clef is perfectly acceptable. When the bassoon ranges into its very highest register, I would much prefer to read these notes in treble.