Physics of Trumpet

By: Kali Aissen


The vibration of your lips is what causes the sound wave in a trumpet. The sound travels through the tubing to the bell. The bell causes resistance at the antinode and reflects back on itself, making the trumpet project its sound.


The vibration of your lips helps to determine the pitch of the sound waves. The tighter you buzz your lips, the higher note you produce. The looser you buzz your lips, the lower note you produce. The combination of the buzzing of your lips and a strong, steady air stream helps you to play notes.


The bell of the trumpet helps to determine the frequency of the sound waves. The trumpet is a high brass instrument, so it has shorter sound waves. You’re able to hear shorter sound waves easier than lower ones. The bell also causes the trumpet to have a directional sound.

Mouthpiece and Leadpipe

With the help of the mouthpiece and leadpipe, the trumpet is able to produce a sound of 800 hertz. The higher the note you play, the shorter the wave and the higher the frequency. The lower the notes you play, the lower the waves and the lower the frequency.


Sound Wave: a wave of rarefaction and compression

Wavelength: one wave cycle

Amplitude: volume, measured from rest to crest

Frequency: wave cycles per second


  • Place mouthpiece in leadpipe

  • Make a ‘farting’ noise with your lips (This is buzzing)

  • Buzz into the trumpet mouth piece attached to the leadpipe

  • Try tightening your buzz or loosening it to make different pitches

  • Try taking the bell out to see a difference in the projection