A soprano clarinet is a clarinet that is higher in register than the basset horn or alto clarinet. The unmodified word clarinet usually refers to the B♭ clarinet, which is by far the most common type. The term soprano also applies to the clarinets in A and C, and even the low G clarinet—rare in Western music but popular in the folk music of Turkey—which sounds a whole tone lower than the A. Some writers reserve a separate category of sopranino clarinets for the E♭ and D clarinets, while some regarded them as soprano clarinets. All have a written range from the E below middle C to about the C three octaves above middle C, with the sounding pitches determined by the particular instrument's transposition.
Orchestral composers largely write for soprano clarinets in B♭ and A. Clarinets in C were used likewise from the Classical era until about 1910. Wolfgang Amadeus Mozart also called for clarinets in B♮ when writing in keys with many sharps (e.g. the E major arias in Idomeneo and Così fan tutte), but this became obsolete far sooner. There have also been soprano clarinets in C, A, and B♭ with curved barrels and bells marketed under the names Saxonette, Claribel, and Clariphon.
