C clarinet
This instrument became practically obsolete in the orchestras of Europe and the United States in the early twentieth century. The inclusion of the C clarinet, however was not unusual in orchestral scores from the era of Haydn and Mozart right through to the early 20th century. Mahler certainly included them up until his fourth symphony. Much of the orchestral repertoire of Beethoven and Schubert requires the C clarinet. This being the case, the nineteenth century clarinetists were faced with the difficult task of maintaining and alternating between instruments in A, B♭ and C. Since this was not always necessary or desirable for a first rate clarinetist, who could transpose easily between instruments and may not have wished to change from a warm to a cold instrument, the tendency has been to reduce, with the result that the usage of the C clarinet has gradually declined from the standard classical orchestra.
Recently, however, the C clarinet is enjoying a resurgence, as there is now a renewed interest in playing older works on their authentic instruments. This applies to orchestral music and also to popular folk styles such as Klezmer music. At the same time there has been an innovation in Britain to use a simplified cheaper version of the C clarinet, so called clarinéo, as the principal wind instrument for young learners, a position until recently, occupied by the recorder.
The clarinet in C is sometimes called for in clarinet choirs, often as a substitute for the oboe.
*When the composer used the C clarinet it is often for the different tone of the instrument. Transposing the part on the B-Flat clarinet does not sound the same as playing it on the C clarinet.
