The clarinet is a family of woodwind instruments. It has a single-reed mouthpiece, a straight, cylindrical tube with an almost cylindrical bore, and a flared bell. A person who plays a clarinet is called a clarinetist (sometimes spelled clarinettist).

While the similarity in sound between the earliest clarinets and the trumpet may hold a clue to its name, other factors may have been involved. During the Late Baroque era, composers such as Bach and Handel were making new demands on the skills of their trumpeters, who were often required to play difficult melodic passages in the high, or as it came to be called, clarion register.

Defining the top end of a clarinet's range is difficult since many advanced players can produce notes well above the highest notes commonly found in method books.

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