Physics 101
							Like most air using instruments the trumpet uses a reed to produce sound. One's lips are used as a reed to make pressure waves that are compressed into the mouthpiece until it reaches the throat of the mouthpiece. The air does not have to move through the trumpet to produce sound. The air is has two phases maximum pressure (the crest of the wave) and rarefraction ( the bottom of the wave). The air is not moved it is simply vibrated to form different sound patterns. The pressure refraction points are called nodes (spot where there is no movement). The tubal pattern of the trumpet is essential to the sound. Certain pressure points exsist in every note. For example, a G on the treble staff cannot be played with the spit valve open. But an E can be played because the E does not have its nodal pressure point in that valve.
				The three valves on the trumpet work to increase the length of the tubing to lower the pitchs. The first valve of the trumpet works to lower the pitch on whole step. The second a semitone and the third a minor third. The standar length of trumpet tubing (with all valves decompressed) is a 148 cm. When compressing the first valve one adds 17.9 cm. When compressing the second adds 27.8 cm and the third adds 26.5cm. When adding addition length to the valves it causes the note to be lower.
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