What is the sound interval of the Bb clarinet compared to concert pitch?

The Bb clarinet is classified as a transposing instrument, which means it produces a pitch that differs from what is written in the musical score. Specifically, when a player plays a written note on a Bb clarinet, the sound that is produced is actually a whole step lower than the written pitch in concert key.

For example, if the written note is a C on the staff, the actual pitch produced by the Bb clarinet sounds a Bb. Therefore, the sound interval of the Bb clarinet compared to concert pitch is indeed a major second lower. This characteristic is essential for composers and arrangers to understand, as it affects how music is notated for the Bb clarinet and how it interacts with other instruments in a concert setting.

Other options do not accurately describe the relationship between the written notes for the Bb clarinet and the concert pitch. Understanding this concept is crucial for musicians who work with transposing instruments.