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The Bb clarinet is the most commonly used clarinet in professional and amateur bands and orchestras. It produces the highest-pitched notes of the standard clarinet family, and is pitched in the key of Bb. This means that when played in its lowest register, the clarinet produces the note Bb. The Bb clarinet has a range from the lowest note, which is E flat below the staff, to the highest note, which is F# in the altissimo register.