Mechanics of the Trumpet
The principle mechanic of the trumpet, as with all brass instruments, is the pushing of air through the lips (referred to as the embouchure) in order to make them vibrate and create sound. Professional trumpet players are experts at manipulating airspeed and volume of air to vibrate their lips at the correct frequency.
While air flow is the most important part of playing the trumpet, the pitches must be decided by an outside factor. Simply buzzing the lips through the end of the trumpet does not produce a scale or etude. In ancient times, buglers or trumpet players manipulated pitches by increasing or decreasing their airspeed. This alone created the pitches that were so vital to the army, or that entertained royalty in the court. In the modern era, trumpet players still use air flow, but in a different way.
The modern valved trumpet has a harmonic series, which means that with every valve combination there is a set of pitches that can be played. As mentioned before, this is how modern trumpet players use airflow. They change between “partials” (pitches in a harmonic series) and use valve combinations in different partials to reach all the notes that can be played with that valve combination.
The modern trumpet also has a valve series. Each valve pressed down on the trumpet extends its length by a set amount. The 2nd valve is the shortest, 1st is the middle, and 3rd is the longest. Therefore, the valve series from highest to lowest can be written as such, with numbers signifying which valve is to be pressed down: 0, 2, 1, 3, 23, 13, 123. Most trumpet players substitute 12 for 3 in the series because the third valve can create tuning issues.