Semi-Contrabassoon (Bass Bassoon, Great Bassoon?)
This is an instrument pitched midway between the Bassoon and the Contrabassoon. It does not exist. I wish it did. It should be no more difficult to produce than a regular Bassoon. It would not have to be made in the complex folded manner of the Contrabassoon, but rather built as an over-sized Bassoon. These instruments have existed historically, but no modern instrument has ever been constructed.
To give myself an idea of the sound that a Semi-Contrabassoon (I really dislike that name, perhaps if it existed the Bassoon would become the Baritone Bassoon and the Semi-Contra would be the Bass Bassoon) I recorded a Bassoonist and digitally manipulated the sound in a computer. I first dropped the pitch an octave to give the sound of a Contrabassoon, and the results were uncannily similar to the real instrument. I then did the reverse and raised the pitch a fourth and the result was identical to a Tenor Bassoon. With these convincing results, I then dropped the pitch to where a Semi-Contra would be. The sound was beautiful. It was warm and rich without the gruffness of the Contrabassoon. As the Bassoon itself is lacking in flexibility in the low register, these notes are not as used. The pseudo Semi-Contra fixed this problem. I will wait for technology to make my dream a reality (I may be waiting for a long time). If ever built, it would be constructed with new technology being used in some Bassoons and Contrabassoons and a range of up to four octaves should be perfectly conceivable.
If ever constructed, it would be akin to the Contra-Alto Clarinet; a more flexible contrabass member of the family and more readily suited for solos. It could fill in as the third voice in the bassoon family (two Bassoons, Semi-Contra, and Contrabassoon). In this role, it would bridge the large gap in sound between the Bassoon and the Contrabassoon.