The Trumpet consists of a narrow tube of brass coiled round on itself to save space. The sound comes out of the flared bell, and is made by blowing a "raspberry" with your lips into the cup-shaped mouthpiece. In effect, your lips are vibrating like the reed of a clarinet, and this vibration becomes musical sound in its passage through the specially-shaped bore of the trumpet. You can obtain a number of different "open" notes in this way by varying the tension of your lips (try blowing a raspberry and smiling at the same time), and can then produce the notes in between by pressing different combinations of valves. The valves divert the air through little extra lengths of tubing, thus making the instrument temporarily a bit longer and therefore deeper. There are three valves.