* Single-reed design: Unlike most other woodwind instruments, which use a double-reed, the clarinet uses a single-reed. This gives the clarinet a more mellow, warm sound than other woodwinds, and also allows for a wider range of sound production techniques.
* Cylindrical bore: Most woodwind instruments, such as the flute, oboe, and bassoon, have a conical bore, meaning that the diameter of the tube increases as it goes from the mouthpiece to the bell. The clarinet is the only major woodwind instrument with a cylindrical bore, meaning that the diameter of the tube is the same throughout. This gives the clarinet a distinct, focused sound that is different from other woodwind voices.
* Transposing instrument: The clarinet is a transposing instrument, which means that the music written for it is not in the key that it actually sounds in. Clarinets are typically written in B-flat, but sound a whole step lower than written. This is because the clarinet's fundamental note is B-flat, and all of the other notes on the instrument are based on this note.
These are just some of the unique features that make the clarinet a special and distinct musical instrument.