How does a brass instrument make noise?

Answer 1

Brass instruments are different from all the other instruments in that the person playing is solely responsible for the sound of the instrument. Brass instruments require the player to buzz their lips in the mouthpiece. This sound reverberates throughout the instrument and produces the sound that comes out of it. This differs from other instruments, where the player makes part of the instrument vibrate (i.e. reed, string, drum head). The pitch of brass instruments is then changed by changing the frequency of the vibrations created by the lips. If you buzz your lips at a higher pitch, the instrument plays a higher note. The opposite is also true. Buzzing your lips at a lower pitch creates a lower note.