Trombone Notes and Positions | Normans Blog
The trombone is the only brass instrument that doesn’t use valves to change the pitch within a harmonic series of notes. To get all of the pitches, you need change the Harmonic series. This is done by tightening and loosening the tension of your lips, this will create a higher or lower sounding buzz. A high buzz will be created by tight lips and a fast stream of air pushed through them causing a high frequency of vibrations this will result in a produce a high note.