A question arose recently on the Orchestration Online Facebook page about the use of the tenor and treble clefs for the Bassoon. As a Bassoonist, I feel I can clarify this fairly well.
For the first few years of a Bassoonist’s life, they will only read in bass clef. The standard range will be around two and a half octaves from B-flat1 to F 4. This means two ledger lines above and two ledger lines below the bass clef. This is easy. Once the range starts to ascend above this range, then the tenor clef is usually brought in. Occasional high notes can be handled in bass clef, provided that the whole of the tessitura is not in the higher range.
If the passage has a tessitura of around G3 to C5, then the tenor clef is far preferred. Notes below F3 should always be put in the bass clef. Bassoonists do not like reading passages written in the bottom two lines of the tenor clef. Passages below the tenor clef are virtually unheard of (though, the famous Bassoon solo in Shostakovich’s 9th Symphony does go below the tenor clef, this is an anomaly).
In passages in the extreme high register, the treble clef is preferred. This means passages that include the notes E5 to G5. Anything within the tessitura of roughly A4 to G5 is best read in treble. Passages that are better suited for tenor clef should never be written in treble. Many times, inexperienced composers will write their bassoon parts in treble and bass and leave it to the editor or publisher to sort out. This is not a good solution, as often times the publisher will leave the part as is with no changes.
On the physical side of things, Bassoons keep their music stand further away from them than will other wind instruments. This is due to the size of the instrument. This means that the player’s music will be further away and therefore slightly harder to read. This is not usually a problem except when it comes to multiple ledger lines. Anything over 4 ledger lines becomes difficult to read accurately (this would be B4 in bass clef and F5 in tenor). Notes at this height are best taken in the alternative clef.
Switching between the clefs
Rapidly switching between bass and tenor clef can be done as long as it is the clearest and most effective way of writing the passage. Tenor clef for a single note or group of notes can be done if needed, but shouldn’t be done regularly.
Contrabassoon, Tenor, and Alto Bassoons
On occasion, the Contrabassoon will be written in the tenor clef (see Schoenberg’s Chamber Symphony No. 1). This is somewhat antithetical to the point of the Contrabassoon, but when needed, it works. In my own Contrabassoon Concerto, I even wrote passages for the Contra in treble clef (up to a written A-flat5).
The Tenor Bassoon, will use tenor clef as frequently as the regular Bassoon. No issues here.
The Alto Bassoon really has no need for the tenor clef as the highest written note is only F4.