Brass instrument Brass instrument A brass instrument is a musical instrument that produces sound by sympathetic vibration of air in a tubular resonator in sympathy with the vibration of the player's lips. Brass instruments are also called "labrosones", literally meaning "lip-vibrated instruments". There are several factors involved in producing different pitches on a brass instrument. Slides, valves, crooks (though they are rarely used today), or keys are used to change vibratory length of tubing, thus changing the available harmonic series, while the player's embouchure, lip tension and air flow serve to select the specific harmonic produced from the available series. The view
French horn the time, the mouthpiece is placed in the exact center of the lips, but, because of differences in the formation of the lips and teeth of different players, some tend to play with the mouthpiece slightly off center. Although the exact side-to-side placement of the mouthpiece varies for most horn players, the up-and-down placement of the mouthpiece is generally two-thirds on the upper lip and one-third on the lower lip. When playing higher notes, the majority of players exert a small degree of additional pressure on the lips using the mouthpiece. However, this is undesirable from the perspective of both