A rather large member of the clarinet family, the Contrabass Clarinet is in the key of B-flat, and is one octave below the bass clarinet, which in turn is one octave lower than the regular B-flat clarinet.
There are two types of Contrabass Clarinet- the Straight Contra and the Curved Contra. Curved Contrabasses are approximately two and a half feet long and doubles back on it self three, or sometimes four times. The straight contrabass clarinet does not double back on itself, and as a result is well over five feet in length.
The contrabass clarinet is not often used, as it is a rather rare instrument, but when it is used, it usually doubles with the Contrabassoon, or the regular Bassoon.
I play the Contrabass Clarinet in the orchestra.